Medical device inserters and processes of inserting and using medical devices

ABSTRACT

An apparatus for insertion of a medical device in the skin of a subject is provided, as well as methods of inserting medical devices.

RELATED APPLICATIONS

The present application is a continuation of U.S. patent application Ser. No. 16/387,023, filed Apr. 17, 2019, which is a continuation of U.S. patent application Ser. No. 14/884,622, filed Oct. 15, 2015, now U.S. Pat. No. 10,292,632, which is a continuation of U.S. patent application Ser. No. 13/071,497, filed Mar. 24, 2011, now U.S. Pat. No. 9,186,098, which claims the benefit of U.S. Provisional Application Nos. 61/317,243, filed Mar. 24, 2010; 61/345,562, filed May 17, 2010; 61/361,374, filed Jul. 2, 2010; and 61/411,262, filed Nov. 8, 2010, all of which are incorporated herein by reference in their entireties and for all purposes.

INCORPORATION BY REFERENCE

Patents, applications and/or publications described herein, including the following patents, applications and/or publications are incorporated herein by reference for all purposes: U.S. Pat. Nos. 4,545,382; 4,711,245; 5,262,035; 5,262,305; 5,264,104; 5,320,715; 5,356,786; 5,509,410; 5,543,326; 5,593,852; 5,601,435; 5,628,890; 5,820,551; 5,822,715; 5,899,855; 5,918,603; 6,071,391; 6,103,033; 6,120,676; 6,121,009; 6,134,461; 6,143,164; 6,144,837; 6,161,095; 6,175,752; 6,270,455; 6,284,478; 6,299,757; 6,338,790; 6,377,894; 6,461,496; 6,503,381; 6,514,460; 6,514,718; 6,540,891; 6,560,471; 6,579,690; 6,591,125; 6,592,745; 6,600,997; 6,605,200; 6,605,201; 6,616,819; 6,618,934; 6,650,471; 6,654,625; 6,676,816; 6,730,200; 6,736,957; 6,746,582; 6,749,740; 6,764,581; 6,773,671; 6,881,551; 6,893,545; 6,932,892; 6,932,894; 6,942,518; 7,041,468; 7,167,818; and 7,299,082; 7,381,184; 7,740,581; 7,811,231 U.S. Published Application Nos. 2005/0182306; 2006/0091006; 2007/0056858, now U.S. Pat. No. 8,298,389; 2007/0068807, now U.S. Pat. No. 7,846,311; 2007/0095661; 2007/0108048, now U.S. Pat. No. 7,918,975; 2007/0149873; 2007/0149875, now U.S. Pat. No. 8,515,518; 2007/0199818, now U.S. Pat. No. 7,811,430; 2007/0227911, now U.S. Pat. No. 7,887,682; 2007/0233013; 2008/0058625, now U.S. Pat. No. 7,920,907; 2008/0064937; 2008/0066305, now U.S. Pat. No. 7,895,740; 2008/0071157; 2008/0071158; 2008/0081977, now U.S. Pat. No. 7,618,369; 2008/0102441, now U.S. Pat. No. 7,822,557; 2008/0148873, now U.S. Pat. No. 7,802,467; 2008/0161666; 2008/0179187; 2008/0267823; 2008/0319295, now U.S. Pat. No. 8,597,188; 2008/0319296, now U.S. Pat. No. 8,617,069; 2009/0018425, now U.S. Pat. No. 8,160,670; 2009/0247857, now U.S. Pat. No. 8,346,335; 2009/0257911, now U.S. Pat. No. 8,252,229, 2009/0281406; 2009/0294277; 2009/0054748, now U.S. Pat. No. 7,885,698; 2009/0054749; 2010/0030052; 2010/0065441, now U.S. Pat. No. 8,636,884; 2010/0081905; 2010/0081909, now U.S. Pat. No. 8,219,173; 2010/0213057; 2010/0325868, now U.S. Pat. No. 7,866,026; 2010/0326842; 2010/0326843, now U.S. Pat. No. 8,437,827; 2010/0331643; 2011/0046466; U.S. patent application Ser. Nos. 12/624,767; 12/625,185, now U.S. Pat. No. 8,354,013; 12/625,208; 12/625,524, now U.S. Pat. No. 8,390,455; 12/625,525, now U.S. Pat. No. 8,358,210; 12/625,528, now U.S. Pat. No. 8,115,635; 12/628,177; 12/628,198; 12/628,201; 12/628,203; 12/628,210; 12/698,124; 12/698,129; 12/699,653; 12/699,844; 12/714,439; 12/730,193; 12/794,721, now U.S. Pat. No. 8,595,607; 12/807,278; 12/842,013; 12/870,818; 12/871,901, now U.S. Pat. No. 8,514,086; 12/873,301; 12/873,302; 13/011,897; and U.S. Provisional Application Nos. 61/238,646; 61/246,825; 61/247,516; 61/249,535; 61/317,243; 61/325,155; 61/345,562; and 61/359,265.

BACKGROUND OF THE INVENTION

The detection and/or monitoring of glucose levels or other analytes, such as lactate, oxygen, AlC, or the like, in certain individuals is vitally important to their health. For example, the monitoring of glucose is particularly important to individuals with diabetes. Diabetics generally monitor glucose levels to determine if their glucose levels are being maintained within a clinically safe range, and may also use this information to determine if and/or when insulin is needed to reduce glucose levels in their bodies or when additional glucose is needed to raise the level of glucose in their bodies.

Growing clinical data demonstrates a strong correlation between the frequency of glucose monitoring and glycemic control. Despite such correlation, many individuals diagnosed with a diabetic condition do not monitor their glucose levels as frequently as they should due to a combination of factors including convenience, testing discretion, pain associated with glucose testing, and cost.

Devices have been developed for the automatic monitoring of analyte(s), such as glucose, in bodily fluid such as in the blood stream or in interstitial fluid (“ISF”), or other biological fluid. Some of these analyte measuring devices are configured so that at least a portion of the devices are positioned below a skin surface of a user, e.g., in a blood vessel or in the subcutaneous tissue of a user, so that the monitoring is accomplished in vivo.

With the continued development of analyte monitoring devices and systems, there is a need for such analyte monitoring devices, systems, and methods, as well as for processes for manufacturing analyte monitoring devices and systems that are cost effective, convenient, and with reduced pain, provide discreet monitoring to encourage frequent analyte monitoring to improve glycemic control.

SUMMARY

An apparatus for inserting a medical device through the skin of a subject is provided, which includes a housing defining a longitudinal cavity therein and a interference member extending into the cavity; a biasing member; a driver member coupled to the biasing member for movement from a proximal position to a distal position and further configured for movement between a misaligned configuration in which the driver member is impeded from distal movement by the interference member and an aligned configuration in which the driver member is not impeded from distal movement by the interference member; and an actuator having an alignment surface for moving the driver member from the misaligned configuration to the aligned configuration.

In some embodiments, the actuator is movable from a proximal position to a distal position. In some embodiments, distal movement of the actuator compresses the first biasing member. In some embodiments, the first position of the driver member is at an oblique angle with respect to the longitudinal cavity. In some embodiments, the second position of the driver member includes a configuration substantially aligned with the longitudinal cavity.

An apparatus for inserting a medical device through the skin of a subject is provided, which includes a housing defining a cantilever member; a sharp movable within the housing from a retracted position to a partially exposed position; and an electrochemical sensor releasably coupled to the sharp for movement with the sharp, and for subsequent insertion in the skin of a subject; wherein the cantilever member resiliently contacts at least one of the sharp and the sensor.

In some embodiments, the housing includes a distal opening for release of the electrochemical sensor therefrom. In some embodiments, the housing defines a longitudinal notch for reception of a drive member of an inserter. In some embodiments, the housing contains a desiccant. In some embodiments, the housing defines one or more longitudinal ridges for aligning one of the sharp and the sensor.

These and other features, objects, and advantages of the disclosed subject matter will become apparent to those persons skilled in the art upon reading the detailed description as more fully described below.

BRIEF DESCRIPTION OF THE DRAWINGS

A detailed description of various aspects, features, and embodiments of the subject matter described herein is provided with reference to the accompanying drawings, which are briefly described below. The drawings are illustrative and are not necessarily drawn to scale, with some components and features being exaggerated for clarity. The drawings illustrate various aspects and features of the present subject matter and may illustrate one or more embodiment(s) or example(s) of the present subject matter in whole or in part.

FIG. 1 illustrates an analyte monitoring system for real time analyte (e.g., glucose) measurement, data acquisition and/or processing in certain embodiments;

FIGS. 2-3 are views of an electrochemical sensor in accordance with a further embodiment of the disclosed subject matter;

FIGS. 4-5 are schematic views of a needle hub in accordance with one embodiment of the disclosed subject matter;

FIG. 6 is a distal end view of a sharp in accordance with one embodiment of the disclosed subject matter;

FIG. 7 is a side view of a sharp in accordance with one embodiment of the disclosed subject matter;

FIG. 8 is a side view of a sharp in accordance with one embodiment of the disclosed subject matter;

FIG. 9 is a perspective view of a sharp in accordance with one embodiment of the disclosed subject matter;

FIG. 10 is a schematic view of an alternate embodiment for forming a sharp to be used in an inserter in accordance with one embodiment of the disclosed subject matter;

FIG. 11 is a perspective view of an inserter in accordance with one embodiment of the disclosed subject matter;

FIG. 12 is a perspective view with parts separated of an inserter in accordance with one embodiment of the disclosed subject matter;

FIG. 13 is an enlarged sectional view with parts separated of an inserter in accordance with one embodiment of the disclosed subject matter;

FIG. 14 is a side view of another inserter in accordance with the disclosed subject matter;

FIGS. 15-17 are sectional, perspective views of the inserter of FIG. 14 in accordance with another embodiment of the disclosed subject matter;

FIG. 18 is a perspective view of another inserter in accordance with the disclosed subject matter;

FIGS. 19-21 are side views with transparency of the inserter of FIG. 18 in accordance with another embodiment of the disclosed subject matter;

FIG. 22 is a perspective view of another inserter in accordance with the disclosed subject matter;

FIGS. 23-25 are sectional, perspective views of the inserter of FIG. 22 in accordance with another embodiment of the disclosed subject matter;

FIG. 26 is a sectional view in section of another embodiment of an inserter in accordance with the disclosed subject matter;

FIG. 27 is a perspective view of the inserter of FIG. 26 in accordance with the disclosed subject matter;

FIGS. 28-31 are perspective views of components of the inserter of FIG. 26 in accordance with the disclosed subject matter;

FIG. 32 illustrates an exploded view of the inserter of FIG. 26 in accordance with the disclosed subject matter;

FIG. 33 is a side view of the inserter of FIG. 26 in accordance with the disclosed subject matter;

FIGS. 34-36 are side views with transparency of the inserter of FIG. 26 in accordance with the disclosed subject matter;

FIG. 37 is an inserter in accordance with another embodiment in accordance with the disclosed subject matter;

FIG. 38 is a perspective view in section of the inserter of FIG. 37 in accordance with the disclosed subject matter;

FIG. 39 is a cross-sectional view of the inserter of FIG. 37 in accordance with the disclosed subject matter;

FIG. 40 is a side view of the inserter of FIG. 37 in accordance with the disclosed subject matter;

FIGS. 41-44 are perspective views of components of the inserter of FIG. 37 in accordance with the disclosed subject matter;

FIG. 45 is an exploded view of the inserter of FIG. 37 in accordance with the disclosed subject matter;

FIG. 46 is a side view with transparency of the inserter of FIG. 37 in accordance with the disclosed subject matter;

FIGS. 47-51 are perspective views of another inserter in accordance with the disclosed subject matter;

FIG. 52 is an exploded perspective view of another embodiment of the disclosed subject matter;

FIG. 53 is a sectional view of an inserter in accordance with the disclosed subject matter;

FIGS. 54-55 are perspective views from below of the inserter of FIG. 53;

FIG. 56 is a perspective view of another inserter in accordance with the disclosed subject matter;

FIGS. 57-60 are perspective views of various components of the inserter of FIG. 56;

FIG. 61-62 are perspective views of various components of the inserter of FIG. 56;

FIGS. 63-65 depict different subassemblies of the components of the inserter of FIG. 56;

FIGS. 66-67 are cross-sectional views of a subassembly of the components of the inserter of FIG. 56;

FIGS. 68-70 depict the steps used to actuate the inserter of FIG. 56;

FIG. 71 is a perspective view of an inserter assembly in accordance with the disclosed subject matter;

FIG. 72 is a perspective view of a component of an inserter assembly of FIG. 71 in accordance with the disclosed subject matter;

FIG. 73 is a perspective view of a component of an analyte measurement system in accordance with the disclosed subject matter;

FIG. 74 is a perspective view with parts separated of the inserter assembly of FIG. 71 in accordance with the disclosed subject matter;

FIG. 75 is a cross-sectional view of the inserter assembly of FIG. 71 in accordance with the disclosed subject matter;

FIG. 76 is a side view of a portion of an inserter assembly in accordance with the disclosed subject matter;

FIG. 77 is a view of an analyte sensor in accordance with the disclosed subject matter;

FIGS. 78-79 are perspective views of a portion of an inserter assembly in accordance with the disclosed subject matter;

FIGS. 80-90 are views of analyte sensors in accordance with the disclosed subject matter;

FIGS. 91-92 are cross-sectional views of an inserter assembly in accordance with the disclosed subject matter;

FIGS. 93-94 are cross-sectional views of another inserter assembly in accordance with the disclosed subject matter;

FIGS. 95-96 are cross-sectional views of a further inserter assembly in accordance with the disclosed subject matter;

FIGS. 97-98 are views of a portion of an inserter assembly in accordance with the disclosed subject matter;

FIG. 99 is a cross-sectional view of a portion of an inserter assembly in accordance with the disclosed subject matter;

FIGS. 100-101 are perspective views of a portion of an inserter assembly in accordance with the disclosed subject matter;

FIGS. 102-105 are side views of various inserter assemblies in accordance with the disclosed subject matter;

FIGS. 106-112 are views of a sharp and sharp carrier in accordance with the disclosed subject matter;

FIG. 113 is a perspective view of a portion of an inserter assembly in accordance with the disclosed subject matter;

FIGS. 114-117 are perspective views illustrating the operation of an inserter assembly in accordance with the disclosed subject matter;

FIG. 118 is a side view of an inserter assembly in accordance with the disclosed subject matter;

FIGS. 119-121 are cross-sectional views of an inserter assembly in accordance with the disclosed subject matter;

FIG. 122 is a perspective view with parts separated of an embodiment of a sharp/sensor cartridge in accordance with the disclosed subject matter;

FIG. 123 is a perspective view of the cartridge of FIG. 122 in a first stage of deployment in accordance with the disclosed subject matter;

FIG. 124 is a cross-sectional view of the cartridge of FIG. 122 in a neutral state in accordance with the disclosed subject matter;

FIG. 125 is a perspective view of the cartridge of FIG. 122 in a neutral state in accordance with the disclosed subject matter;

FIG. 126 is a cross-sectional view of the cartridge of FIG. 122 in a first stage of deployment in accordance with the disclosed subject matter;

FIG. 127 is a perspective view of the cartridge of FIG. 122 in a second stage of deployment in accordance with the disclosed subject matter;

FIG. 128 is a cross-sectional view of the cartridge of FIG. 122 in a second stage of deployment in accordance with the disclosed subject matter;

FIG. 129 is a perspective view of the cartridge of FIG. 122 in a third stage of deployment in accordance with the disclosed subject matter;

FIG. 130 is a cross-sectional view of the cartridge of FIG. 122 in a third stage of deployment in accordance with the disclosed subject matter;

FIG. 131 is a perspective view with parts separated of another embodiment of a component of an inserter in accordance with the disclosed subject matter;

FIG. 132 is a perspective view of the cartridge of FIG. 131 in a neutral state in accordance with the disclosed subject matter;

FIG. 133 is a cross-sectional view of the cartridge of FIG. 131 in a neutral state in accordance with the disclosed subject matter;

FIG. 134 is a perspective view of the cartridge of FIG. 131 in a second stage of deployment in accordance with the disclosed subject matter;

FIG. 135 is a cross-sectional view of the cartridge of FIG. 131 in a second stage of deployment in accordance with the disclosed subject matter;

FIG. 136 is a perspective view of the cartridge of FIG. 131 in a third stage of deployment in accordance with the disclosed subject matter; and

FIG. 137 is a cross-sectional view of the cartridge of FIG. 131 in a third stage of deployment in accordance with the disclosed subject matter.

DETAILED DESCRIPTION OF THE EMBODIMENTS

A detailed description of the disclosure is provided herein. It should be understood, in connection with the following description, that the subject matter is not limited to particular embodiments described, as the particular embodiments of the subject matter may, of course, vary. It is also to be understood that the terminology used herein is for the purpose of describing particular embodiments only, and is not intended to be limiting, since the scope of the disclosed subject matter will be limited only by the appended claims.

Where a range of values is provided, it is understood that each intervening value between the upper and lower limit of that range, and any other stated or intervening value in that stated range, is encompassed within the disclosed subject matter. Every range stated is also intended to specifically disclose each and every “subrange” of the stated range. That is, each and every range smaller than the outside range specified by the outside upper and outside lower limits given for a range, whose upper and lower limits are within the range from said outside lower limit to said outside upper limit (unless the context clearly dictates otherwise), is also to be understood as encompassed within the disclosed subject matter, subject to any specifically excluded range or limit within the stated range. Where a range is stated by specifying one or both of an upper and lower limit, ranges excluding either or both of those stated limits, or including one or both of them, are also encompassed within the disclosed subject matter, regardless of whether or not words such as “from,” “to,” “through,” or “including” are or are not used in describing the range.

Unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this disclosed subject matter belongs. Although any methods and materials similar or equivalent to those described herein can also be used in the practice or testing of the present disclosed subject matter, this disclosure may specifically mention certain exemplary methods and materials.

All publications mentioned in this disclosure are, unless otherwise specified, incorporated by reference herein for all purposes, including without limitation to disclose and describe the methods and/or materials in connection with which the publications are cited.

The publications discussed herein are provided solely for their disclosure prior to the filing date of the present application. Nothing herein is to be construed as an admission that the present disclosed subject matter is not entitled to antedate such publication by virtue of prior invention. Further, the dates of publication provided may be different from the actual publication dates, which may need to be independently confirmed.

As used herein and in the appended claims, the singular forms “a,” “an,” and “the” include plural referents unless the context clearly dictates otherwise.

Nothing contained in the Abstract or the Summary should be understood as limiting the scope of the disclosure. The Abstract and the Summary are provided for bibliographic and convenience purposes and due to their formats and purposes should not be considered comprehensive.

As will be apparent to those of skill in the art upon reading this disclosure, each of the individual embodiments described and illustrated herein has discrete components and features which may be readily separated from or combined with the features of any of the other several embodiments without departing from the scope or spirit of the present disclosed subject matter. Any recited method can be carried out in the order of events recited, or in any other order which is logically possible.

Reference to a singular item includes the possibility that there are plural of the same item present. When two or more items (for example, elements or processes) are referenced by an alternative “or,” this indicates that either could be present separately or any combination of them could be present together except where the presence of one necessarily excludes the other or others.

Generally, embodiments of the present disclosure relate to an apparatus for inserting a medical device at least partially into the skin of the patient. Some embodiments relate to in vivo methods and devices for detecting at least one analyte such as glucose in body fluid. Accordingly, embodiments include in vivo analyte sensors configured so that at least a portion of the sensor is positioned in the body of a user (e.g., within the ISF), to obtain information about at least one analyte of the body, e.g., transcutaneously positioned in user's body. In certain embodiments, an in vivo analyte sensor is coupled to an electronics unit that is maintained on the body of the user to process information obtained from the sensor.

In certain embodiments, analyte information is communicated from a first device such as an on body electronics unit to a second device which may include user interface features, including a display, and/or the like. Information may be communicated from the first device to the second device automatically and/or continuously when the analyte information is available, or may not be communicated automatically and/or continuously, but rather stored or logged in a memory of the first device. Accordingly, in many embodiments of the system, analyte information derived by the sensor/on body electronics (for example, on body electronics) is made available in a user-usable or viewable form only when queried by the user such that the timing of data communication is selected by the user. In some embodiments, the display of information is selected by the user, while the timing of data communication is not.

In this manner, analyte information is only provided or evident to a user (provided at a user interface device) in some embodiments when desired by the user even though an in vivo analyte sensor automatically and/or continuously monitors the analyte level in vivo, i.e., the sensor automatically monitors analyte such as glucose on a pre-defined time interval over its usage life. For example, an analyte sensor may be positioned in vivo and coupled to on body electronics for a given sensing period, e.g., about 14 days. In certain embodiments, the sensor-derived analyte information is automatically communicated from the sensor electronics assembly to a remote monitor device or display device for output to a user throughout the 14 day period according to a schedule programmed at the on body electronics (e.g., about every 1 minute or about every 5 minutes or about every 10 minutes, or the like). In certain embodiments, sensor-derived analyte information is only communicated from the sensor electronics assembly to a remote monitor device or display device at user-determined times, e.g., whenever a user decides to check analyte information. At such times, a communications system is activated, and sensor-derived information is then sent from the on body electronics to the remote device or display device.

In still other embodiments, the information may be communicated from the first device to the second device automatically and/or continuously when the analyte information is available, and the second device stores or logs the received information without presenting or outputting the information to the user. In such embodiments, the information is received by the second device from the first device when the information becomes available (e.g., when the sensor detects the analyte level according to a time schedule). However, the received information is initially stored in the second device and only output to a user interface or an output component of the second device (e.g., display) upon detection of a request for the information on the second device.

Accordingly, in certain embodiments an inserter as described herein is used to place a sensor electronics assembly on the body so that at least a portion of the in vivo sensor is in contact with bodily fluid such as ISF. Once the sensor is electrically coupled to the electronics unit, sensor derived analyte information may be communicated from the on body electronics to a display device on-demand by powering on the display device (or it may be continually powered), and executing a software algorithm stored in and accessed from a memory of the display device, to generate one or more request commands, control signal or data packet to send to the on body electronics. The software algorithm executed under, for example, the control of the microprocessor or application specific integrated circuit (ASIC) of the display device may include routines to detect the position of the on body electronics relative to the display device to initiate the transmission of the generated request command, control signal and/or data packet.

Display devices may also include programming stored in memory for execution by one or more microprocessors and/or ASICs to generate and transmit the one or more request command, control signal or data packet to send to the on body electronics in response to a user activation of an input mechanism on the display device such as depressing a button on the display device, triggering a soft button associated with the data communication function, and so on. The input mechanism may be alternatively or additionally provided on or in the on body electronics which may be configured for user activation. In certain embodiments, voice commands or audible signals may be used to prompt or instruct the microprocessor or ASIC to execute the software routine(s) stored in the memory to generate and transmit the one or more request command, control signal or data packet to the on body device. In the embodiments that are voice activated or responsive to voice commands or audible signals, on body electronics and/or display device includes a microphone, a speaker, and processing routines stored in the respective memories of the on body electronics and/or the display device to process the voice commands and/or audible signals. In certain embodiments, positioning the on body electronics and the display device within a predetermined distance (e.g., close proximity) relative to each other initiates one or more software routines stored in the memory of the display device to generate and transmit a request command, control signal or data packet.

Different types and/or forms and/or amounts of information may be sent for each on demand reading, including but not limited to one or more of current analyte level information (i.e., real time or the most recently obtained analyte level information temporally corresponding to the time the reading is initiated), rate of change of an analyte over a predetermined time period, rate of the rate of change of an analyte (acceleration in the rate of change), historical analyte information corresponding to analyte information obtained prior to a given reading and stored in memory of the assembly. Some or all of real time, historical, rate of change, rate of rate of change (such as acceleration or deceleration) information may be sent to a display device for a given reading. In certain embodiments, the type and/or form and/or amount of information sent to a display device may be preprogrammed and/or unchangeable (e.g., preset at manufacturing), or may not be preprogrammed and/or unchangeable so that it may be selectable and/or changeable in the field one or more times (e.g., by activating a switch of the system, etc.). Accordingly, in certain embodiments, for each on demand reading, a display device will output a current (real time) sensor-derived analyte value (e.g., in numerical format), a current rate of analyte change (e.g., in the form of an analyte rate indicator such as an arrow pointing in a direction to indicate the current rate), and analyte trend history data based on sensor readings acquired by and stored in memory of on body electronics (e.g., in the form of a graphical trace). Additionally, the on skin or sensor temperature reading or measurement associated with each on demand reading may be communicated from the on body electronics to the display device. The temperature reading or measurement, however, may not be output or displayed on the display device, but rather, used in conjunction with a software routine executed by the display device to correct or compensate the analyte measurement output to the user on the display device.

As described, embodiments include inserters for in vivo analyte sensors and on body electronics that together provide body wearable sensor electronics assemblies. In certain embodiments, in vivo analyte sensors are fully integrated with on body electronics (fixedly connected during manufacture), while in other embodiments they are separate but connectable post manufacture (e.g., before, during or after sensor insertion into a body). On body electronics may include an in vivo glucose sensor, electronics, battery, and antenna encased (except for the sensor portion that is for in vivo positioning) in a waterproof housing that includes or is attachable to an adhesive pad. In certain embodiments, the housing withstands immersion in about one meter of water for up to at least 30 minutes. In certain embodiments, the housing withstands continuous underwater contact, e.g., for longer than about 30 minutes, and continues to function properly according to its intended use, e.g., without water damage to the housing electronics where the housing is suitable for water submersion.

Embodiments include sensor insertion devices, which also may be referred to herein as sensor delivery units, or the like. Insertion devices may retain on body electronics assemblies completely in an interior compartment, i.e., an insertion device may be “pre-loaded” with on body electronics assemblies during the manufacturing process (e.g., on body electronics may be packaged in a sterile interior compartment of an insertion device). In such embodiments, insertion devices may form sensor assembly packages (including sterile packages) for pre-use or new on body electronics assemblies, and insertion devices configured to apply on body electronics assemblies to recipient bodies.

Embodiments include portable handheld display devices, as separate devices and spaced apart from an on body electronics assembly, that collect information from the assemblies and provide sensor derived analyte readings to users. Such devices may also be referred to as meters, readers, monitors, receivers, human interface devices, companions, or the like. Certain embodiments may include an integrated in vitro analyte meter. In certain embodiments, display devices include one or more wired or wireless communications ports such as USB, serial, parallel, or the like, configured to establish communication between a display device and another unit (e.g., on body electronics, power unit to recharge a battery, a PC, etc.). For example, a display device communication port may enable charging a display device battery with a respective charging cable and/or data exchange between a display device and its compatible informatics software.

Compatible informatics software in certain embodiments include, for example, but not limited to stand alone or network connection enabled data management software program, resident or running on a display device, personal computer, a server terminal, for example, to perform data analysis, charting, data storage, data archiving and data communication as well as data synchronization. Informatics software in certain embodiments may also include software for executing field upgradable functions to upgrade firmware of a display device and/or on body electronics unit to upgrade the resident software on the display device and/or the on body electronics unit, e.g., with versions of firmware that include additional features and/or include software bugs or errors fixed, etc. Embodiments may include a haptic feedback feature such as a vibration motor or the like, configured so that corresponding notifications (e.g., a successful on-demand reading received at a display device), may be delivered in the form of haptic feedback.

Embodiments include programming embedded on a computer readable medium, i.e., computer-based application software (may also be referred to herein as informatics software or programming or the like) that processes analyte information obtained from the system and/or user self-reported data. Application software may be installed on a host computer such as a mobile telephone, PC, an Internet-enabled human interface device such as an Internet-enabled phone, personal digital assistant, or the like, by a display device or an on body electronics unit. Informatics programming may transform data acquired and stored on a display device or on body unit for use by a user.

Embodiments of the subject disclosure are described primarily with respect to glucose monitoring devices and systems, and methods of glucose monitoring, for convenience only and such description is in no way intended to limit the scope of the disclosure. It is to be understood that the analyte monitoring system may be configured to monitor a variety of analytes at the same time or at different times.

As described in detail below, embodiments include devices, systems, kits and/or methods to monitor one or more physiological parameters such as, for example, but not limited to, analyte levels, temperature levels, heart rate, user activity level, over a predetermined monitoring time period. Also provided are methods of manufacturing. Predetermined monitoring time periods may be less than about 1 hour, or may include about 1 hour or more, e.g., about a few hours or more, e.g., about a few days of more, e.g., about 3 or more days, e.g., about 5 days or more, e.g., about 7 days or more, e.g., about 10 days or more, e.g., about 14 days or more, e.g., about several weeks, e.g., about 1 month or more. In certain embodiments, after the expiration of the predetermined monitoring time period, one or more features of the system may be automatically deactivated or disabled at the on body electronics assembly and/or display device.

For example, a predetermined monitoring time period may begin with positioning the sensor in vivo and in contact with a body fluid such as ISF, and/or with the initiation (or powering on to full operational mode) of the on body electronics. Initialization of on body electronics may be implemented with a command generated and transmitted by a display device in response to the activation of a switch and/or by placing the display device within a predetermined distance (e.g., close proximity) to the on body electronics, or by user manual activation of a switch on the on body electronics unit, e.g., depressing a button, or such activation may be caused by the insertion device, e.g., as described in U.S. patent application Ser. No. 12/698,129 filed on Feb. 1, 2010 and U.S. Provisional Application Nos. 61/238,646, 61/246,825, 61/247,516, 61/249,535, 61/317,243, 61/345,562, and 61/361,374, the disclosures of each of which are incorporated herein by reference for all purposes.

When initialized in response to a received command from a display device, the on body electronics retrieves and executes from its memory software routine to fully power on the components of the on body electronics, effectively placing the on body electronics in full operational mode in response to receiving the activation command from the display device. For example, prior to the receipt of the command from the display device, a portion of the components in the on body electronics may be powered by its internal power supply such as a battery while another portion of the components in the on body electronics may be in powered down or maintained in a low power state including no power state, inactive mode, or all components may be in an inactive, powered down mode. Upon receipt of the command, the remaining portion (or all) of the components of the on body electronics is switched to active, fully operational mode.

Embodiments of on body electronics may include one or more printed circuit boards with electronics including control logic implemented in ASIC, microprocessors, memory, and the like, and transcutaneously positionable analyte sensors forming a single assembly. On body electronics may be configured to provide one or more signals or data packets associated with a monitored analyte level upon detection of a display device of the analyte monitoring system within a predetermined proximity for a period of time (for example, about 2 minutes, e.g., 1 minute or less, e.g., about 30 seconds or less, e.g., about 10 seconds or less, e.g., about 5 seconds or less, e.g., about 2 seconds or less) and/or until a confirmation, such as an audible and/or visual and/or tactile (e.g., vibratory) notification, is output on the display device indicating successful acquisition of the analyte related signal from the on body electronics. A distinguishing notification may also be output for unsuccessful acquisition in certain embodiments.

In certain embodiments, the monitored analyte level may be correlated and/or converted to glucose levels in blood or other fluids such as ISF. Such conversion may be accomplished with the on body electronics, but in many embodiments will be accomplished with display device electronics. In certain embodiments, glucose level is derived from the monitored analyte level in the ISF.

Analyte sensors may be insertable into a vein, artery, or other portion of the body containing analyte. In certain embodiments, analyte sensors may be positioned in contact with ISF to detect the level of analyte, where the detected analyte level may be used to infer the user's glucose level in blood or interstitial tissue.

Embodiments include transcutaneous sensors and also wholly implantable sensors and wholly implantable assemblies in which a single assembly including the analyte sensor and electronics are provided in a sealed housing (e.g., hermetically sealed biocompatible housing) for implantation in a user's body for monitoring one or more physiological parameters.

Embodiments include analyte monitors that are provided in small, lightweight, battery-powered and electronically-controlled systems. Such systems may be configured to detect physical parameters of subjects, such as signals indicative of in vivo analyte levels using an electrochemical sensor, and collect such signals, with or without processing. Any suitable measurement technique may be used to obtain signals from the sensors, e.g., may detect current, may employ potentiometry, etc. Techniques may include, but are not limited to amperometry, coulometry, and voltammetry. In some embodiments, sensing systems may be optical, colorimetric, and the like. In some embodiments, the portion of the system that performs this initial processing may be configured to provide the raw or at least initially processed data to another unit for further collection and/or processing. Such provision of data may be affected, for example, by a wired connection, such as an electrical, or by a wireless connection, such as an IR or RF connection.

In certain systems, the analyte sensor is in communication with on body electronics. The on-body unit may include a housing in which the on body electronics and at least a portion of the sensor are received.

Certain embodiments are modular. The on-body unit may be separately provided as a physically distinct assembly from a monitor unit, e.g., which displays or otherwise indicates analyte levels to a user. The on-body unit may be configured to provide the analyte levels detected by the sensor and/or other information (such as temperature, sensor life, etc.) over a communication link to the monitor unit. The monitor unit, in some embodiments, may include, e.g., a mobile telephone device, an in vitro glucose meter, a personal digital assistant, or other consumer electronics such as MP3 device, camera, radio, personal computer, etc., or other communication-enabled data-processing device.

The display unit may perform a variety of functions such as but not limited to data storage and/or processing and/or analysis and/or communication, etc., on the received analyte data to generate information pertaining to the monitored analyte levels and/or process the other information. The monitor unit may incorporate a display screen, which can be used, for example, to display measured analyte levels, and/or an audio component such as a speaker to audibly provide information to a user, and/or a vibration device to provide tactile feedback to a user. It is also useful for a user of an analyte-monitoring system to be able to see trend indications (including the magnitude and direction of any ongoing trend, e.g., the rate of change of an analyte or other parameter, and the amount of time a subject is above and/or below a threshold, such as a hypoglycemic and/or hyperglycemic threshold, etc.); such data may be displayed either numerically, or by a visual indicator such as an arrow that may vary in visual attributes, like size, shape, color, animation, or direction. The monitor unit may further be adapted to receive information from or about an in vitro analyte test strip, which may be manually or automatically entered into the monitor unit. In some embodiments, a monitor unit may incorporate an in vitro analyte test strip port and related electronics in order to be able to make discrete (e.g., blood glucose) measurements using an in vitro test strip (see, e.g., U.S. Pat. No. 6,175,752, the disclosure of which is incorporated by reference herein for all purposes).

The modularity of these systems may vary where one or more components may be constructed to be single use and one or more may be constructed to be re-useable. In some embodiments, the sensor is designed to be attachable and detachable from the on body electronics (and the on-body unit may be reusable), e.g., so that one or more of the components may be reused one or more times, while in other embodiments, the sensor and on body electronics may be provided as an integrated, undetachable package, which may be designed to be disposable after use, i.e., not re-used.

Embodiments of In Vivo Monitoring Systems

For purpose of illustration, and not limitation, the inserters described herein may be used in connection with an exemplary analyte monitoring system as depicted in FIG. 1. It is understood that the inserters described herein may be used with any medical device on its own or in connection with a system. FIG. 1 shows an exemplary in vivo-based analyte monitoring system 100 in accordance with embodiments of the present disclosure. As shown, in certain embodiments, analyte monitoring system 100 includes on body electronics 1100 electrically coupled to in vivo analyte sensor 14 (a proximal portion of which is shown in FIG. 1), and attached to adhesive layer 218 for attachment on a skin surface on the body of a user. On body electronics 1100 includes on body housing 122 that defines an interior compartment.

Also shown in FIG. 1 is insertion device 200 (or insertion devices 300, 400, 2400, 2500, 2700, 3700 described herein) that, when operated, transcutaneously positions a portion of analyte sensor 14 through a skin surface and in fluid contact with ISF, and positions on body electronics 1100 and adhesive layer 218 on a skin surface, as will be described in greater detail herein. In certain embodiments, on body electronics 1100, analyte sensor 14 and adhesive layer 218 are sealed within the housing of insertion device 200 before use, and in certain embodiments, adhesive layer 218 is also sealed within the housing or the adhesive layer can provide a seal for preserving the sterility of the apparatus. Additional details regarding insertion devices are discussed, e.g., in U.S. patent application Ser. No. 12/698,129 and U.S. Provisional Application Nos. 61/238,646, 61/246,825, 61/247,516, 61/249,535, and 61/345,562, the disclosures of each of which are incorporated herein by reference for all purposes.

Referring back to the FIG. 1, analyte monitoring system 100 includes display device 1200 which includes a display 1220 to output information to the user, an input component 1210 such as a button, actuator, a touch sensitive switch, a capacitive switch, pressure sensitive switch, jog wheel or the like, to input data or command to display device 1200 or otherwise control the operation of display device 1200. It is noted that some embodiments may include display-less devices or devices without any user interface components. These devices may be functionalized to store data as a data logger and/or provide a conduit to transfer data from on body electronics and/or a display-less device to another device and/or location. Embodiments will be described herein as display devices for exemplary purposes which are in no way intended to limit the embodiments of the present disclosure. It will be apparent that display-less devices may also be used in certain embodiments.

In certain embodiments, on body electronics 1100 may be configured to store some or all of the monitored analyte related data received from analyte sensor 14 in a memory during the monitoring time period, and maintain it in memory until the usage period ends. In such embodiments, stored data is retrieved from on body electronics 1100 at the conclusion of the monitoring time period, for example, after removing analyte sensor 14 from the user by detaching on body electronics 1100 from the skin surface where it was positioned during the monitoring time period. In such data logging configurations, real time monitored analyte level is not communicated to display device 1200 during the monitoring period or otherwise transmitted from on body electronics 1100, but rather, retrieved from on body electronics 1100 after the monitoring time period.

In certain embodiments, input component 1210 of display device 1200 may include a microphone and display device 1200 may include software configured to analyze audio input received from the microphone, such that functions and operation of the display device 1200 may be controlled by voice commands. In certain embodiments, an output component of display device 1200 includes a speaker for outputting information as audible signals. Similar voice responsive components such as a speaker, microphone and software routines to generate, process and store voice driven signals may be provided to on body electronics 1100.

In certain embodiments, display 1220 and input component 1210 may be integrated into a single component, for example a display that can detect the presence and location of a physical contact touch upon the display such as a touch screen user interface. In such embodiments, the user may control the operation of display device 1200 by utilizing a set of pre-programmed motion commands, including, but not limited to, single or double tapping the display, dragging a finger or instrument across the display, motioning multiple fingers or instruments toward one another, motioning multiple fingers or instruments away from one another, etc. In certain embodiments, a display includes a touch screen having areas of pixels with single or dual function capacitive elements that serve as LCD elements and touch sensors.

Display device 1200 also includes data communication port 1230 for wired data communication with external devices such as remote terminal (personal computer) 1700, for example. Example embodiments of the data communication port 1230 include USB port, mini USB port, RS-232 port, Ethernet port, Firewire port, or other similar data communication ports configured to connect to the compatible data cables. Display device 1200 may also include an integrated in vitro glucose meter, including in vitro test strip port 1240 to receive an in vitro glucose test strip for performing in vitro blood glucose measurements.

Referring still to FIG. 1, display 1220 in certain embodiments is configured to display a variety of information—some or all of which may be displayed at the same or different time on display 1220. In certain embodiments the displayed information is user-selectable so that a user can customize the information shown on a given display screen. Display 1220 may include but is not limited to graphical display 1380, for example, providing a graphical output of glucose values over a monitored time period (which may show important markers such as meals, exercise, sleep, heart rate, blood pressure, etc, numerical display 1320, for example, providing monitored glucose values (acquired or received in response to the request for the information), and trend or directional arrow display 1310 that indicates a rate of analyte change and/or a rate of the rate of analyte change, e.g., by moving locations on display 1220.

As further shown in FIG. 1, display 1220 may also include date display 1350 providing for example, date information for the user, time of day information display 1390 providing time of day information to the user, battery level indicator display 1330 which graphically shows the condition of the battery (rechargeable or disposable) of the display device 1200, sensor calibration status icon display 1340 for example, in monitoring systems that require periodic, routine or a predetermined number of user calibration events, notifying the user that the analyte sensor calibration is necessary, audio/vibratory settings icon display 1360 for displaying the status of the audio/vibratory output or alarm state, and wireless connectivity status icon display 1370 that provides indication of wireless communication connection with other devices such as on body electronics, data processing module 1600, and/or remote terminal 1700. As additionally shown in FIG. 1, display 1220 may further include simulated touch screen button 1250, 1260 for accessing menus, changing display graph output configurations or otherwise for controlling the operation of display device 1200.

Referring back to FIG. 1, in certain embodiments, display 1220 of display device 1200 may be additionally, or instead of visual display, configured to output alarms notifications such as alarm and/or alert notifications, glucose values etc, which may be audible, tactile, or any combination thereof. In one aspect, the display device 1200 may include other output components such as a speaker, vibratory output component and the like to provide audible and/or vibratory output indication to the user in addition to the visual output indication provided on display 1220. Further details and other display embodiments can be found in, e.g., U.S. patent application Ser. No. 12/871,901, U.S. Provisional Application Nos. 61/238,672, 61/247,541, 61/297,625, the disclosures of each of which are incorporated herein by reference for all purposes.

After the positioning of on body electronics 1100 on the skin surface and analyte sensor 14 in vivo to establish fluid contact with ISF (or other appropriate body fluid), on body electronics 1100 in certain embodiments is configured to wirelessly communicate analyte related data (such as, for example, data corresponding to monitored analyte level and/or monitored temperature data, and/or stored historical analyte related data) when on body electronics 1100 receives a command or request signal from display device 1200. In certain embodiments, on body electronics 1100 may be configured to at least periodically broadcast real time data associated with monitored analyte level which is received by display device 1200 when display device 1200 is within communication range of the data broadcast from on body electronics 1100, i.e., it does not need a command or request from a display device to send information.

For example, display device 1200 may be configured to transmit one or more commands to on body electronics 1100 to initiate data transfer, and in response, on body electronics 1100 may be configured to wirelessly transmit stored analyte related data collected during the monitoring time period to display device 1200. Display device 1200 may in turn be connected to a remote terminal 1700 such as a personal computer and functions as a data conduit to transfer the stored analyte level information from the on body electronics 1100 to remote terminal 1700. In certain embodiments, the received data from the on body electronics 1100 may be stored (permanently or temporarily) in one or more memory of the display device 1200. In certain other embodiments, display device 1200 is configured as a data conduit to pass the data received from on body electronics 1100 to remote terminal 1700 that is connected to display device 1200.

Referring still to FIG. 1, also shown in analyte monitoring system 100 are data processing module 1600 and remote terminal 1700. Remote terminal 1700 may include a personal computer, a server terminal a laptop computer or other suitable data processing devices including software for data management and analysis and communication with the components in the analyte monitoring system 100. For example, remote terminal 1700 may be connected to a local area network (LAN), a wide area network (WAN), or other data network for uni-directional or bi-directional data communication between remote terminal 1700 and display device 1200 and/or data processing module 1600.

Remote terminal 1700 in certain embodiments may include one or more computer terminals located at a physician's office or a hospital. For example, remote terminal 1700 may be located at a location other than the location of display device 1200. Remote terminal 1700 and display device 1200 could be in different rooms or different buildings. Remote terminal 1700 and display device 1200 could be at least about one mile apart, e.g., at least about 100 miles apart, e.g., at least about 1000 miles apart. For example, remote terminal 1700 could be in the same city as display device 1200, remote terminal 1700 could be in a different city than display device 1200, remote terminal 1700 could be in the same state as display device 1200, remote terminal 1700 could be in a different state than display device 1200, remote terminal 1700 could be in the same country as display device 1200, or remote terminal 1700 could be in a different country than display device 1200, for example.

In certain embodiments, a separate, optional data communication/processing device such as data processing module 1600 may be provided in analyte monitoring system 100. Data processing module 1600 may include components to communicate using one or more wireless communication protocols such as, for example, but not limited to, infrared (IR) protocol, Bluetooth® protocol, Zigbee® protocol, and 802.11 wireless LAN protocol. Additional description of communication protocols including those based on Bluetooth® protocol and/or Zigbee® protocol can be found in U.S. Patent Publication No. 2006/0193375 incorporated herein by reference for all purposes. Data processing module 1600 may further include communication ports, drivers or connectors to establish wired communication with one or more of display device 1200, on body electronics 1100, or remote terminal 1700 including, for example, but not limited to USB connector and/or USB port, Ethernet connector and/or port, FireWire connector and/or port, or RS-232 port and/or connector.

In certain embodiments, data processing module 1600 is programmed to transmit a polling or query signal to on body electronics 1100 at a predetermined time interval (e.g., once every minute, once every five minutes, or the like), and in response, receive the monitored analyte level information from on body electronics 1100. Data processing module 1600 stores in its memory the received analyte level information, and/or relays or retransmits the received information to another device such as display device 1200. More specifically in certain embodiments, data processing module 1600 may be configured as a data relay device to retransmit or pass through the received analyte level data from on body electronics 1100 to display device 1200 or a remote terminal (for example, over a data network such as a cellular or WiFi data network) or both.

In certain embodiments, on body electronics 1100 and data processing module 1600 may be positioned on the skin surface of the user within a predetermined distance of each other (for example, about 1-12 inches, or about 1-10 inches, or about 1-7 inches, or about 1-5 inches) such that periodic communication between on body electronics 1100 and data processing module 1600 is maintained. Alternatively, data processing module 1600 may be worn on a belt or clothing item of the user, such that the desired distance for communication between the on body electronics 1100 and data processing module 1600 for data communication is maintained. In a further aspect, the housing of data processing module 1600 may be configured to couple to or engage with on body electronics 1100 such that the two devices are combined or integrated as a single assembly and positioned on the skin surface. In further embodiments, data processing module 1600 is detachably engaged or connected to on body electronics 1100 providing additional modularity such that data processing module 1600 may be optionally removed or reattached as desired.

Referring again to FIG. 1, in certain embodiments, data processing module 1600 is programmed to transmit a command or signal to on body electronics 1100 at a predetermined time interval such as once every minute, or once every 5 minutes or once every 30 minutes or any other suitable or desired programmable time interval to request analyte related data from on body electronics 1100. When data processing module 1600 receives the requested analyte related data, it stores the received data. In this manner, analyte monitoring system 100 may be configured to receive the continuously monitored analyte related information at the programmed or programmable time interval, which is stored and/or displayed to the user. The stored data in data processing module 1600 may be subsequently provided or transmitted to display device 1200, remote terminal 1700 or the like for subsequent data analysis such as identifying frequency of periods of glycemic level excursions over the monitored time period, or the frequency of the alarm event occurrence during the monitored time period, for example, to improve therapy related decisions. Using this information, the doctor, healthcare provider or the user may adjust or recommend modification to the diet, daily habits and routines such as exercise, and the like.

In another embodiment, data processing module 1600 transmits a command or signal to on body electronics 1100 to receive the analyte related data in response to a user activation of a switch provided on data processing module 1600 or a user initiated command received from display device 1200. In further embodiments, data processing module 1600 is configured to transmit a command or signal to on body electronics 1100 in response to receiving a user initiated command only after a predetermined time interval has elapsed. For example, in certain embodiments, if the user does not initiate communication within a programmed time period, such as, for example about 5 hours from last communication (or 10 hours from the last communication, or 24 hours from the last communication), the data processing module 1600 may be programmed to automatically transmit a request command or signal to on body electronics 1100. Alternatively, data processing module 1600 may be programmed to activate an alarm to notify the user that a predetermined time period of time has elapsed since the last communication between the data processing module 1600 and on body electronics 1100. In this manner, users or healthcare providers may program or configure data processing module 1600 to provide certain compliance with analyte monitoring regimen, so that frequent determination of analyte levels is maintained or performed by the user.

In certain embodiments, when a programmed or programmable alarm condition is detected (for example, a detected glucose level monitored by analyte sensor 14 that is outside a predetermined acceptable range indicating a physiological condition) which requires attention or intervention for medical treatment or analysis (for example, a hypoglycemic condition, a hyperglycemic condition, an impending hyperglycemic condition or an impending hypoglycemic condition), the one or more output indications may be generated by the control logic or processor of the on body electronics 1100 and output to the user on a user interface of on body electronics 1100 so that corrective action may be timely taken. In addition to or alternatively, if display device 1200 is within communication range, the output indications or alarm data may be communicated to display device 1200 whose processor, upon detection of the alarm data reception, controls the display 1220 to output one or more notification.

In certain embodiments, control logic or microprocessors of on body electronics 1100 include software programs to determine future or anticipated analyte levels based on information obtained from analyte sensor 14, e.g., the current analyte level, the rate of change of the analyte level, the acceleration of the analyte level change, and/or analyte trend information determined based on stored monitored analyte data providing a historical trend or direction of analyte level fluctuation as function time during monitored time period. Predictive alarm parameters may be programmed or programmable in display device 1200, or the on body electronics 1100, or both, and output to the user in advance of anticipating the user's analyte level reaching the future level. This provides the user an opportunity to take timely corrective action.

Information, such as variation or fluctuation of the monitored analyte level as a function of time over the monitored time period providing analyte trend information, for example, may be determined by one or more control logic or microprocessors of display device 1200, data processing module 1600, and/or remote terminal 1700, and/or on body electronics 1100. Such information may be displayed as, for example, a graph (such as a line graph) to indicate to the user the current and/or historical and/or and predicted future analyte levels as measured and predicted by the analyte monitoring system 100. Such information may also be displayed as directional arrows (for example, see trend or directional arrow display 1310) or other icon(s), e.g., the position of which on the screen relative to a reference point indicated whether the analyte level is increasing or decreasing as well as the acceleration or deceleration of the increase or decrease in analyte level. This information may be utilized by the user to determine any necessary corrective actions to ensure the analyte level remains within an acceptable and/or clinically safe range. Other visual indicators, including colors, flashing, fading, etc., as well as audio indicators including a change in pitch, volume, or tone of an audio output and/or vibratory or other tactile indicators may also be incorporated into the display of trend data as means of notifying the user of the current level and/or direction and/or rate of change of the monitored analyte level. For example, based on a determined rate of glucose change, programmed clinically significant glucose threshold levels (e.g., hyperglycemic and/or hypoglycemic levels), and current analyte level derived by an in vivo analyte sensor, the system 100 may include an algorithm stored on computer readable medium to determine the time it will take to reach a clinically significant level and will output notification in advance of reaching the clinically significant level, e.g., 30 minutes before a clinically significant level is anticipated, and/or 20 minutes, and/or 10 minutes, and/or 5 minutes, and/or 3 minutes, and/or 1 minute, and so on, with outputs increasing in intensity or the like.

Referring again back to FIG. 1, in certain embodiments, software algorithm(s) for execution by data processing module 1600 may be stored in an external memory device such as an SD card, microSD card, compact flash card, XD card, Memory Stick card, Memory Stick Duo card, or USB memory stick/device including executable programs stored in such devices for execution upon connection to the respective one or more of the on body electronics 1100, remote terminal 1700 or display device 1200. In a further aspect, software algorithms for execution by data processing module 1600 may be provided to a communication device such as a mobile telephone including, for example, WiFi or Internet enabled smart phones or personal digital assistants (PDAs) as a downloadable application for execution by the downloading communication device.

Examples of smart phones include Windows®, Android™, iPhone® operating system, Palm® WebOS™, Blackberry® operating system, or Symbian® operating system based mobile telephones with data network connectivity functionality for data communication over an internet connection and/or a local area network (LAN). PDAs as described above include, for example, portable electronic devices including one or more microprocessors and data communication capability with a user interface (e.g., display/output unit and/or input unit, and configured for performing data processing, data upload/download over the internet, for example. In such embodiments, remote terminal 1700 may be configured to provide the executable application software to the one or more of the communication devices described above when communication between the remote terminal 1700 and the devices are established.

In still further embodiments, executable software applications may be provided over-the-air (OTA) as an OTA download such that wired connection to remote terminal 1700 is not necessary. For example, executable applications may be automatically downloaded as software download to the communication device, and depending upon the configuration of the communication device, installed on the device for use automatically, or based on user confirmation or acknowledgement on the communication device to execute the installation of the application. The OTA download and installation of software may include software applications and/or routines that are updates or upgrades to the existing functions or features of data processing module 1600 and/or display device 1200.

Referring back to remote terminal 1700 of FIG. 1, in certain embodiments, new software and/or software updates such as software patches or fixes, firmware updates or software driver upgrades, among others, for display device 1200 and/or on body electronics 1100 and/or data processing module 1600 may be provided by remote terminal 1700 when communication between the remote terminal 1700 and display device 1200 and/or data processing module 1600 is established. For example, software upgrades, executable programming changes or modification for on body electronics 1100 may be received from remote terminal 1700 by one or more of display device 1200 or data processing module 1600, and thereafter, provided to on body electronics 1100 to update its software or programmable functions. For example, in certain embodiments, software received and installed in on body electronics 1100 may include software bug fixes, modification to the previously stalled software parameters (modification to analyte related data storage time interval, resetting or adjusting time base or information of on body electronics 1100, modification to the transmitted data type, data transmission sequence, or data storage time period, among others). Additional details describing field upgradability of software of portable electronic devices, and data processing are provided in U.S. application Ser. Nos. 12/698,124, 12/794,721, now U.S. Pat. No. 8,595,607, 12/699,653, and 12/699,844, and U.S. Provisional Application Nos. 61/359,265, and 61/325,155 the disclosures of which are incorporated by reference herein for all purposes.

The Sensor

The analyte sensor 14 of the analyte measurement system 100 may be used to monitor levels of a wide variety of analytes. Analytes that may be monitored include, for example, acetylcholine, amylase, bilirubin, cholesterol, chorionic gonadotropin, creatine kinase (e.g., CK-MB), creatine, DNA, fructosamine, glucose, glutamine, growth hormones, hormones, ketones, lactate, peroxide, prostate-specific antigen, prothrombin, RNA, thyroid-stimulating hormone, and troponin. The concentration of drugs, such as, for example, antibiotics (e.g., gentamicin, vancomycin, and the like), digitoxin, digoxin, drugs of abuse, theophylline, and warfarin, may also be monitored. One or more analyte may be monitored by a given sensor. In those embodiments that monitor more than one analyte, the analytes may be monitored at the same or different times, which may use the same on body electronics (e.g., simultaneously) or with different on body electronics.

In one embodiment of the present disclosure, sensor 14 is physically positioned in or on the body of a user whose analyte level is being monitored. Sensor 14 may be configured to continuously sample the analyte level of the user and convert the sampled analyte level, e.g., glucose concentration into a corresponding data signal, e.g., a current or voltage, for input into on body electronics. Alternatively, sensor 14 may be configured to sample analyte levels on demand. The on body electronics may amplify, filter, average, and/or otherwise process signal provided by the sensor.

An embodiment of the sensor 14 is illustrated in FIG. 2. It is understood that the inserters described herein can be used with other medical devices. The shape(s) described herein are exemplary only. Other sensor shapes are contemplated. In some embodiments, sensor 14 includes a substrate which is a dielectric, e.g., a polymer or plastic material, such as polyester or polyamide. In this embodiment, the sensor is constructed so that a portion is positionable beneath skin and a portion is above skin. Accordingly, sensor 14 includes an insertion or internal portion 30 and an external or electrical contact portion 32. In some embodiments, the contact portion 32 includes several conductive contacts 36, 38, and 40 (herein shown as three contacts) for connection to other electronics, e.g., at the on body electronics 1100 (See FIG. 1). The contacts provided in this embodiment are for a working electrode, a reference electrode, and a counter electrode. In some embodiments, two or more working electrodes are provided. The operative portions of these electrodes, that is, working electrode, reference electrode, and counter electrode (not individually shown), are provided at the insertion portion, e.g., at the distal end of insertion portion 30, e.g., portion 34. In some embodiments, one or more electrodes may be external to the body, e.g., an external counter electrode. The contact and operative portions of the electrodes are connected by circuit traces 42, 44, and 46 running on the surface of the substrate. In some embodiments, the traces are provided in channels, or may be embedded within the substrate, or may traverse different sides of the substrate. The conductive contacts, conductive traces, and electrodes are fabricated from conductive material, such as platinum, palladium, gold, carbon, or the like. More than one material may be used for a given sensor. Further details of sensors are described, e.g., in U.S. Pat. Nos. 6,175,572 and 6,103,033, which are incorporated by reference herein for all purposes.

Sensor 14 may include a proximal retention portion 48. The insertion portion 30 and the proximal retention portion 48 are sized and configured to be positioned with a sharp for installation into the skin of a subject, as described herein. In use, the sensor 14 may be configured to bend (e.g., along the line B) and therefore be positioned in two substantially perpendicular, intersecting planes. Such bending may occur prior to or during coupling to the on body electronics as described below (See FIG. 17).

Portions 48 and 52 provide a path for electrical connections, e.g., the conductive traces, between the proximal and distal portions of the sensor. Sensor 14 is further provided with a notch or cut-out 54. Such configuration facilitates the sensor 14 to bend (e.g., along the line indicated by line B) such that retention portion 48 remains upright and therefore be positioned in two substantially perpendicular, intersecting planes, as illustrated in FIG. 3. As will be described below, the sensor tab 50 can be encased in the on body housing 122 to aid in securing and positioning the sensor 14. Proximal retention portion 48 maintains its longitudinal alignment with insertion portion 30 for positioning within an insertion sharp.

Embodiments of analyte sensors have been described herein to operate electrochemically, through an arrangement of electrodes having chemical sensing layers applied thereto, by generating an electrical current proportional to the volume of a redox reaction of the analyte (and indicative of analyte concentration), catalyzed by an analyte-specific oxidizing enzyme. Embodiments exist in which the number of electrodes provided to bring about and detect the level of these reactions is two, three, or a greater number. However, other types of sensors may be employed as described herein.

A portion of sensor 14 may be situated above the surface of the skin, with a distal portion 30 penetrating through the skin and into the subcutaneous space in contact with the user's biofluid, such as ISF. Further details regarding the electrochemistry of sensor 14 is provided in U.S. Pat. Nos. 5,264,104; 5,356,786; 5,262,035; 5,320,725; and 6,990,366, each of which is incorporated by reference herein for all purposes.

In some embodiments, the sensor is implantable into a subject's body for a usage period (e.g., a minute or more, at least one day or more, about one to about 30 days or even longer, about three to about fourteen days, about three to about seven days, or in some embodiments, longer periods of up to several weeks) to contact and monitor an analyte present in a biological fluid. In this regard, the sensor can be disposed in a subject at a variety of sites (e.g., abdomen, upper arm, thigh, etc.), including intramuscularly, transcutaneously, intravascularly, or in a body cavity.

In some embodiments, sensor 14 is employed by insertion and/or implantation into a user's body for some usage period. In such embodiments, the substrate may be formed from a relatively flexible material.

While the embodiments illustrated in FIGS. 2-3 have three electrodes, other embodiments can include a fewer or greater number of electrodes. For example, a two-electrode sensor can be utilized. The sensor 14 may be externally-powered and allow a current to pass which is proportional to the amount of analyte present. Alternatively, the sensor 14 itself may act as a current source in some embodiments. In some two-electrode embodiments, the sensor may be self-biasing and there may be no need for a reference electrode. An exemplary self-powered, two-electrode sensor is described in U.S. patent application Ser. No. 12/393,921, filed Feb. 26, 2009, and entitled “Self-Powered Analyte Sensor,” which is hereby incorporated by reference herein for all purposes. The level of current provided by a self-powered sensor may be low, for example, on the order of nanoamperes, in certain embodiments.

Insertion Assembly

Insertion assemblies are provided which are used to install a medical device to the subject. In some embodiments, an insertion assembly includes an inserter and the medical device itself. The inserter can be configured to insert various medical devices into the subject, such as, for example, an analyte sensor, an infusion set, or a cannula. In some embodiments, the inserter can be configured to install a combination of such devices, e.g., a combined sensor/infusion set, etc., at the same or different times or locations. For example, in certain embodiments, a given inserter can be configured to install a first device and a second device at different times. In this regard, the inserter can be reusable. For example, an inserter may be modifiable to be used with more than one medical device, to include more than one type of medical device, e.g., by attaching an adapter and/or detaching a portion of an inserter. The inserter can install the medical device in, under, or through the skin of the subject, or place the medical device on the surface of the skin. The medical device can include features or structures, e.g., barbs, tabs, adhesive, etc., to maintain the device in position with respect to the skin after insertion. The inserter device may also be used as a lancet, e.g., to pierce the skin without inserting or installing a medical device.

In some embodiments, an insertion assembly includes an inserter, a medical device, such as an analyte sensor, and a mount for supporting the medical device at least partially in or on the skin of the subject. In some embodiments, the mount is a support structure, plate and/or member which is attached, adhered, or otherwise secured to the skin of the subject. The mount may be inserted simultaneously with the medical device by the inserter. In other embodiments, the mount is installed after or before installation of the medical device. A mount may be applied by the inserter or separately. The mount may include features or structures (e.g., adhesive, guides, barbs, tabs, etc.) to maintain the sensor in position with respect to the skin after insertion and/or maintain the sensor in relative position with respect to the sensor control unit. In some embodiments, an adhesive pad or strip is used to secure the medical device, e.g., the sensor and/or the sensor control unit, and no mount is used.

In some embodiments, an insertion assembly includes an inserter, an analyte sensor, a mount, and a power supply. The mount and power supply may be inserted simultaneously with the analyte sensor by the inserter. In other embodiments, the mount and battery are installed after or before installation of the analyte sensor. In such case, the mount and/or power supply may be applied by the inserter or separately. The power supply may be used to provide a current or a potential to the sensor and/or to provide power for communication of one or more signals to the monitor unit.

In some embodiments, an insertion assembly includes an inserter, a medical device such as an analyte sensor, a mount, and a sensor control unit. The mount and sensor control unit may be deployed and/or installed simultaneously with the analyte sensor by the inserter. In other embodiments, the mount and sensor control unit are installed after or before installation of the analyte sensor. For example, the mount and the analyte sensor may be installed by the inserter, and the sensor control unit may be subsequently installed. In other embodiments, the mount is installed, followed by insertion of the analyte sensor by the inserter, and further followed by installation of the sensor control unit. In other embodiments, the mount and sensor control unit are installed first, and the analyte sensor is subsequently installed.

In some embodiments, electronics of the sensor control unit provide a voltage or current to the analyte sensor. In some embodiments, the electronics processes signals are provided by the analyte sensor. In further embodiments, the electronics may include communication functionality for providing signal relating to signal provided by the analyte sensor to a further component, such as, e.g., a monitor unit, a computer, or other component. In some embodiments, communications circuitry, such as RFID antenna or other communications circuitry, is provided. The power supply may be used to power some or all of these functions. In some embodiments, power is provided from the monitor unit, e.g., via inductive coupling.

An inserter may include a plurality of different components. For example, an inserter may include one or more components for advancing a sharp towards the skin of the subject. The sensor and sensor control unit and/or mounting structure may be supported by a support structure, such as a carriage. A driver may be provided for advancing the sharp and/or the analyte sensor/support structure. In some embodiments, the actuator is directly or indirectly coupled to the sharp and/or support structure, such that manual force and speed applied by the subject to the actuator is transferred to the sharp and/or support structure. In some embodiments, the applied force drives the sharp and/or support structure between a retracted position and an advanced position. In some embodiments, the sensor and sensor control unit and/or mounting structure is maintained in a retracted position prior to installation by contacting projections extending inwardly from a sheath. In accordance with this embodiment, the sensor and sensor control unit and/or mounting structure are temporarily maintained operatively between the support structure and the projections disposed on the interior wall of the sheath.

An inserter can also include one or more components for retracting the sharp, while allowing the analyte sensor and optional mount and/or electronics to remain on the subject. The components for retracting the sharp can include a retractor. It is understood that the retractor and the actuator may be the same structure or include some common components. In some embodiments, the retractor is directly or indirectly coupled to the sharp such that the manual force applied by the user is transferred from the retractor to the sharp to retract the sharp from the skin. In other embodiments, a drive assembly may be provided to retract the sharp. For example, the drive assembly may include a spring, motor, hydraulic piston, etc., to retract the sharp away from the skin of the subject. The drive assembly may also include a linear drive component.

In some embodiments, the retractor withdraws the sharp upon actuation by the user. In such cases, the user actuates the retractor when it is desired to withdraw the sharp. For example, the retractor may include a release switch. Upon activation of the release switch, the drive assembly, e.g., the spring or other driver, retracts the sharp from the skin. In other embodiments, the retractor and the actuator include common components. After activating the actuator to advance the sharp and the analyte sensor, the user releases the actuator, which allows the drive assembly to withdraw the sharp from the skin.

In some embodiments, the retractor withdraws the sharp without further user interaction after actuation of insertion. For example, the inserter may include features or components which automatically retract the sharp upon advancement of the sharp and support structure by a predetermined amount. Inserter devices, in which no further action by the user is required to initiate withdrawal of the sharp after insertion, are referred to herein as having “automatic” withdrawal of the sharp.

Inserter Devices

One embodiment of a needle hub for an inserter is illustrated in FIGS. 4-5. Needle hub 136 supports sharp 124, having a sharpened distal portion 160. In some embodiments, as discussed herein, a longitudinal wall opening or gap 162 is provided in at least a portion of the wall of the sharp 124. The length N of the gap 162 is selected to be commensurate with the length of the insertion portion 30 through to the proximal retention portion 48 of the sensor, and in certain embodiments may be about 3 mm to about 50 mm, e.g., about 5 mm, or about 10 mm, or about 15 mm, or about 20 mm. The length L of the sharp 124 may be about 3 mm to about 50 mm, e.g., 5 mm or more, or about 10 mm, or about 20 mm, or about 30 mm, or about 50 mm, and is selected based upon the length of the insertion portion 30 of a sensor and the desired depth of the insertion portion 30 of the sensor 14. In some embodiments, the distance or spacing between the two edges of the gap is about 0.2 mm to about 0.5 mm, e.g., about 0.22 mm, about 0.25 mm, etc.

The distal portion 160 of sharp 124 is illustrated in greater detail in FIGS. 6-8. As illustrated in FIG. 6, sharp 124 has a substantially “C”- or “U”-shaped profile in this embodiment, but may have other configurations, e.g., substantially “V”-shaped. A longitudinal gap 162 is provided in the wall of the sharp 124. FIG. 7 illustrates distal portion 160 as provided with an angled tip. In some embodiments, the angled tip may be provided with a first angled tip portion 164 and a second steep-angled tip portion 166. The exemplary configuration, which includes multiple edges and faces, provides a sharp point to reduce penetration force, trauma, and bleeding for the subject. The distal section of the sensor body has a width sized to fit within the gap 162 of the insertion sharp 124 having a diameter less than about 20 gauge to about 26 gauge, e.g., 21 gauge to about 25 gauge, where in certain embodiments the sharp is 21 gauge or 23 gauge or 25 gauge. Such sharp may be used with a sensor having a width or diameter—at least the portion that is carried by the sharp—of about 0.20 mm to about 0.80 mm, e.g., about 0.25 mm to about 0.60 mm, where, in some embodiments, the width or diameter of at least a portion of a sensor is 0.27 mm or 0.33 mm or 0.58 mm. In some embodiments, sharp 124 is fabricated from a sheet of metal and folded into a substantially “V,” “U” or “C” configuration in cross-section. Various technologies can be used to manufacture a folded sheet of metal to form sharp 124. For example, etched-sheet metal technology can be used to form the sharp 124. In this manner, the sharp can be formed having a very sharp edge so that penetration through the skin during insertion is less painful. In other embodiments, a progressive die technology may be utilized to form a complex sheet-metal shape that has a sharp edge as depicted in FIG. 9. In some embodiments, the sharp 124 can be molded with a plastic cap so that the sharp can be handled during the inserter assembly process. Further, the die cut sharp may be molded with plastic to reinforce the “V,” “U” or “C” shaped sheet metal configuration. In other embodiments, a laser-cut sharp can be formed. In this manner, the laser can be used to form the wall opening or gap 162 and first-angled tip portion 164 and a second, steep-angled tip portion 166.

In another embodiment, a sharp 124 may be formed from a standard hypodermic needle utilizing the method depicted in FIG. 10. First, the hypodermic needle (having a circular cross-section) is cut to the desired length for sharp 124. Next, the hypodermic needle is compressed so that its cross-section is permanently deformed from a circular shape to an oval shape. The tip of the hypodermic needle is then ground to a bevel to produce a sharp point to reduce the required penetration force, as previously discussed. Finally, the top section of the needle is removed by appropriate techniques (e.g., grinding, electropolishing, etc.). The resulting sharp 124 has a “U”-shaped configuration and provides ample space for the insertion of sensor 14. In some embodiments, the tip-grinding step and the compression step may be carried out in reversed order.

Due to the compression step, a user may initially start with a larger diameter hypodermic needle so that the finished sharp 124 will have similar dimensions to the previously described sharps.

FIGS. 11-12 illustrate the position of on body housing 122 with respect to the needle hub 136 and sharp 124. The on body housing 122 can be configured to hold at least a portion of sensor 14 and sensor control unit. As illustrated in FIG. 11, the sharp 124 extends through an aperture 168 in the on body housing 122. Thus, in some embodiments, the sharp 124 is uncoupled to on body housing 122. The distal portion of sensor 14 is positioned within the sharp 124. As further illustrated in FIG. 12, electronics of the sensor control unit (e.g., a printed circuit board containing electronics components of the on-body unit) and sensor hub 123 are positioned within on body housing 122. Sensor 14 may include a positioning structure, or slit 127, which receives a positioning member, such as tab 129 of sensor hub 123. A power supply 82, such as a battery, e.g., a single use disposable battery, or rechargeable battery, is provided. The power supply 82 is used to provide potential or current to the sensor in some embodiments. In embodiments where a passive communications protocol such as passive RFID is used, no power supply is provided for the communications. Such power is provided by the monitor unit. In some embodiments, where the sensor control unit is used to transmit one or more signals, one or more power supplies may be used to provide power for such communications circuitry. In some embodiments, the active operational life of the battery may exceed the active operational life of the sensor 14.

FIG. 13 illustrates in cross-section the orientation of the on body housing 122 with respect to the sharp 124 of an inserter, such as inserter 1500 (see FIG. 52). As discussed herein, sensor 14 is disposed in a substantially bent configuration in some embodiments, such that a portion of the sensor, e.g., the insertion portion 30 and the proximal retention portion 48, are substantially vertical (e.g., substantially aligned with the longitudinal axis of an inserter and substantially perpendicular to the skin surface) and the contact portion 32 (shown in profile) is oriented in a substantially horizontal configuration, and in electrical contact with the data-processing unit electronics, such as circuit 80. The sensor tab 50 can be encased in the plastic of the on body housing 122 (e.g., “overmolded”) and secured in place. The notch 56 provides further stability to the sensor 14, e.g., by allowing the sensor tab 50 to be encased by the material of the on body housing 122, and further provides a means for vertically orienting the sensor 14 during mounting, e.g., by allowing vertical positioning of the notch 56 with respect to a vertical landmark of the on body housing 122.

The sensor 14, mounted with the on body housing 122, can be disposed within a recess of the carriage 130 such as a concave recess in the carriage 130. Alternatively, the sensor 14, mounted with the on body housing 122, can be disposed between the support structure and one or more projections extending from the wall of the sheath. In yet another alternative, the sensor 14, mounted with the on body housing 122, can be held in position by a releasable friction fit coupling to the sharp 124. In this manner, the carriage need not have a recess within which the sensor mounted with the on body housing is disposed. In the initial configuration of the inserter, the sharp 124 extends through a longitudinal aperture 168 formed in a carriage 130. In some embodiments, the aperture 168 is appropriately sized, such that neither the sharp 124 nor needle hub 136 is in contact with the carriage 130. Accordingly, the needle hub 136 (and sharp 124) on the one hand, and the carriage 130 (FIG. 13) and the on body housing 122, on the other hand, move simultaneously, but independently from one another. In other embodiments, a friction fit may be provided between the aperture and the sharp.

The insertion portion 30 and proximal retention portion 48 of the sensor 14 are disposed within a longitudinal bore 162 within the sharp 124 (See, e.g., FIG. 6). The proximal retention portion 48 is disposed within the longitudinal bore of the sharp 124 and provides additional stability to the mounting of the sensor 14 within the sharp 124. The longitudinal wall gap or opening 162 of sharp 124 is aligned with the sensor 14, such that the tab 50 and the contact portion 32 extend laterally outward from the sharp 124.

An embodiment of an inserter is illustrated in FIGS. 14-17. An inserter 900 includes a handle 902 and may include a removable distal cap or seal (not shown) for maintaining a sterile environment for the medical device and sharp housed therein. As illustrated in FIG. 14, distal cap or seal is removed from handle 902. Inserter 900 includes a base 942 that defines a distal surface 912 for placement on the skin of a subject. Inserter 900 may be utilized to advance a medical device into the skin of the subject. In some embodiments, handle 902 is advanced relative to base 942 in order to advance the sensor into the skin of the patient.

As illustrated in FIG. 15, the inserter 900 includes an initial configuration in which the handle 902 is disposed in a proximal position with respect to the base 942. In such configuration, the sharp 924 is disposed in a configuration spaced apart from the aperture 920 of the adhesive layer 918. Extending distally from the upper surface of handle 902 are side walls 974, which terminate in a shoulder portion 975.

Needle carrier 934 is axially slidable within handle 902 and base 942 in the direction of arrow N. Needle carrier 934 supports needle hub 936, from which sharp 924 extends longitudinally within the inserter 900. In some embodiments, the sharp is supported at an oblique angle, e.g., between 0° and 90° with respect to the skin surface. Initially, needle carrier 934 is coupled to inner rail 928 through inter-engagement of finger 986 of needle carrier 934 with shoulder 987 of inner rail 928.

Inserter 900 includes an advancement spring 947. Inner rail 928 includes a spring retention portion 984 for advancement spring 947. The inner surface of handle 902 serves as an upper engagement surface for advancement spring 947. In some embodiments, spring retention portion 984 is fabricated having several projections that extend through an aperture 982 in the wall of base 942. Spring retention portion 984 is resiliently movable. As downward force is applied to handle 902, the ledge 937 of handle 902 contacts spring retention portion 984, driving such projections inward. Such inward motion releases the inner rail 928, and allows advancement spring 947 to advance the inner rail 928 distally, thereby advancing the sharp 924 into the skin of the subject, as illustrated in FIG. 16.

Retraction spring 946 is disposed between spring retention portion 948 of base 942 and shoulder portion 949 of needle carrier 934. Initially, retraction spring 946 is in a compressed state. As carriage 930 reaches a distal position, the distal surface of the on body housing 122 engages the upper surface of adhesive pad 918, thereby becoming adhered to the skin surface S of the subject. At the same time, flanges 970 of base 942 engage fingers 986 disposed on the needle carrier 934. Fingers 986 are pivoted outwards by flanges 970. Such pivoting of fingers causes fingers 986 to become disengaged from shoulder 984 of inner rail 928. Shuttle 934 is thereby disengaged from inner rail 928.

As illustrated in FIG. 17, disengagement of the shuttle 934 from the inner rail 928 permits the spring 946 to expand, thereby advancing the needle carrier 934 to a proximal position, thereby withdrawing the sharp 924 from the skin of the subject, while leaving the sensor 14 in the skin.

A further embodiment of an inserter is illustrated in FIGS. 18-21 and designated inserter 1000. Inserter 1000 is substantially identical to inserter 900 described herein, with the substantial differences noted herein and illustrated in the accompanying figures.

An inserter 1000 includes a housing 1002, and may include a removable distal cap or seal (not shown) for maintaining a sterile environment for the medical device and sharp housed therein. As illustrated in FIG. 18, distal cap or seal is removed from housing 1002. Inserter 1000 includes a base 1042 which defines a distal surface 1012 for placement on the skin of a subject. Inserter 1000 may be utilized to advance a medical device into the skin of the subject. In some embodiments, side buttons 1084 are depressed relative to base 1042 in order to advance the medical device into the skin of the patient.

As illustrated in FIG. 19, the inserter 1000 includes an initial configuration in which the sharp 1024 is disposed in a configuration spaced apart from distal portion 1012 of the base 1042. It is understood that inserter 1000 may incorporate an adhesive layer (not shown) positioned across the distal portion 1012 of base 1042.

On-body unit inserter 1028 includes carriage 1030 for supporting on body housing 122. On-body unit inserter 1028 also includes flange 1029 which normally rests on shoulder portions 1086 (as illustrated in FIGS. 19-21). When side buttons 1084 are depressed inwardly, latch portions on flange 1029 are deflected from engagement with shoulder portions 1086. As illustrated in FIG. 20, advancement spring 1047 is released from compression, thereby advancing on-body unit inserter 1028 as elsewhere, along with needle carrier 1034 into the skin of the subject.

Retraction spring 1046 is disposed between needle carrier 1034 and housing 1002. Initially, retraction spring 1046 is in a compressed state. As carriage 1028 reaches a distal position, on-body unit inserter 1028 is disengaged from needle carrier 1034. The distal surface of the on body housing 122 engages the skin or the upper surface of adhesive pad (not shown), thereby becoming adhered to the skin surface S of the subject. Latches on needle carrier 1034 attach it to on-body unit inserter 1028. Upon firing the inserter by pressing tabs 1084, the on-body unit inserter 1028 is pushed by spring 1047 towards the skin surface, bringing along needle carrier 1034 and loading extension spring 1046. As on-body unit inserter 1028 reaches the distal position (towards the skin of the subject), protrusions on housing 1002 disengage latches on needle carrier 1034, connecting it to on-body unit inserter 1028. Extension spring 1046 now pulls needle carrier 1034 back into the proximal position.

As illustrated in FIG. 21, disengagement of the needle carrier 1034 from on-body unit inserter 1028 permits the spring 1046 to contract with the bias, thereby advancing the needle carrier 1034 to a proximal position and withdrawing the sharp 1024 from the skin of the subject, while leaving the sensor 14 in the skin.

A further embodiment of an inserter is illustrated in FIGS. 22-25. Inserter 1100B is substantially identical to inserters 900 and 1000 described herein, with the substantial differences noted herein and illustrated in the accompanying figures.

An inserter 1100B includes a housing 1102 and may include a removable distal cap or seal (not shown) for maintaining a sterile environment for the medical device and/or sharp housed therein. As illustrated in FIG. 22, distal cap or seal is removed from housing 1102. Inserter 1100B includes a base 1142 which defines a distal surface 1112 for placement on the skin of a subject. Inserter 1100B may be utilized to advance a medical device into the skin of the subject. In some embodiments, a manual actuator bar 1114 is depressed relative to base 1142 in order to advance the medical device into the skin of the patient. It is understood that inserter 1100B may incorporate an adhesive layer (not shown) which is positioned across the distal portion 1112 of base 1142.

As illustrated in FIG. 23, the inserter 1100B includes an initial configuration in which the sharp 1124 is disposed in a configuration spaced apart from distal portion 1112 of the base 1142. Manual advancement of the actuator may be performed by distal advancement of actuator bar 1114.

On-body unit inserter 1128A includes carriage 1130 for supporting on body housing 122. Retraction spring 1146 is disposed between needle carrier 1134 and base 1142. Initially, retraction spring 1146 is in a compressed state. As actuator bar 1114 is moved distally, carriage 1130 is moved distally and reaches a distal position, such that flanges 1188 of base 1142 engage fingers 1186 disposed on the shuttle 1134. Fingers 1186 are pivoted outwards by flanges 1188. Such pivoting of fingers 1186 causes fingers 1186 to become disengaged from shoulder 1187 of inner rail 1128. Shuttle 1134 is thereby disengaged from inner rail 1128. The distal surface of the on body housing 122 engages the skin or the upper surface of adhesive pad (not shown), thereby becoming adhered to the skin surface of the subject (FIG. 24).

As illustrated in FIG. 25, disengagement of the shuttle 1134 from the inner rail 1128 permits the spring 1146 to expand with the bias, thereby advancing the needle carrier 1136 to a proximal position and withdrawing the sharp 1124 from the skin of the subject, while leaving the sensor 14 in the skin. Once the sharp 1124 has been withdrawn from the subject, it is no longer accessible from the distal portion of the inserter 1100B, and unable to make contact by accident with the subject's skin.

A further embodiment of an inserter is illustrated in FIGS. 26-36. Inserter 1200 is substantially identical to inserters 900, 1000, and 1100B described herein, with the substantial differences noted herein and illustrated in the accompanying figures.

Inserter 1200 includes a housing 1202, an on-body unit inserter 1228, a needle retractor 1234, an inserter base 1212, and a rotor 1208 with a torsion spring (not shown), all of which are depicted separately in FIGS. 28-31. As illustrated in FIGS. 28-31, housing 1202 includes slots 1254; on-body unit inserter 1228 includes slots 1252, tabs 1253, and opening 1262; needle retractor 1234 includes tabs 1250 and opening 1260; and rotor 1208 includes rotor follower 1264.

FIG. 32 illustrates an exploded view of inserter 1200. As illustrated, in some embodiments, inserter 1200 includes housing 1202, on-body unit inserter 1228, needle retractor 1234, and rotor 1208. Tabs 1250 can be disposed on needle retractor 1234 and configured to engage slots 1252 disposed on on-body unit inserter 1228 when assembled as shown in FIG. 33. Tabs 1253 can be disposed on on-body unit inserter 1228 and configured to engage slots 1254 disposed on housing 1202. Needle retractor 1234 and on-body unit inserter 1228 can each contain openings (1260, 1262) to receive rotor follower 1264 disposed on rotor 1208 after rotor 1208 has been inserted into housing 1202. Additionally, on-body unit inserter 1228 can provide support for on body housing 122 (not shown) for installation to the skin of a subject.

As illustrated in FIG. 34, in some embodiments, manually depressing the on-body unit inserter 1228 can cause the torsion spring to wind as the rotor 1208 rotates, guided by the cam path. As illustrated in FIG. 35, continued distal advancement of the on-body unit inserter 1228 causes the rotor follower 1264 to go “over center” within cam. At such point, the torsion spring (not shown) is allowed to unwind. With reference to FIG. 36, further unwinding of the torsion spring pulls up the needle retractor 1234 from the insertion site, while leaving the on-body unit inserter in place.

A further embodiment of an inserter is illustrated in FIGS. 37-46. Inserter 1300 is substantially identical to inserters 900, 1000, 1100B, and 1200 described herein, with the substantial differences noted herein and illustrated in the accompanying figures.

Inserter 1300 includes a housing 1302, an on-body unit inserter 1334, a needle retractor 1328, and a rotor 1308 with torsion spring 1365. As illustrated in FIGS. 37, 38, 39, 45 and 46, the on-body unit inserter 1334 and needle retractor 1328 are disposed within the housing 1302. Rotor 1308 includes a rotor follower 1364 which engages a slot 1362 provided in the needle retractor 1328 and a slot 1360 in the on-body unit inserter 1334. The on-body unit inserter 1334 provides a support portion for supporting on body housing 1302 (not shown).

In operation, torsion spring 1365 is loaded. A release button (not shown) is depressed in order to release torsion spring 1365. Rotor 1308 drives on-body unit inserter 1334 and needle retractor 1328 downwardly simultaneously. A compression spring 1367 holds down on-body unit inserter 1334. As rotor 1308 continues to rotate, slot 1360 allows on-body unit inserter 1334 to travel down and then be held down, while slot 1362 allows needle retractor 1328 to travel down and then back up to lift the needle from insertion site.

A further embodiment of an inserter is illustrated in FIGS. 47-51. Inserter 1400 is substantially identical to inserters 900, 1000, 1100B, 1200, and 1300 described herein, with the substantial differences noted herein and illustrated in the accompanying figures.

Inserter 1400 may be used for installation of a medical device, e.g., on body housing 122, in connection with a cartridge or carrier 1406. In some embodiments, inserter 1400 includes a body 1402 and an actuator 1404. The carrier 1406 may include a needle hub 1436 including a sharp (not shown) as well as an on body housing 122. In use, the body 1402 is placed on a mount 1408 attached to subject by use of an adhesive pad 1418. As shown in FIG. 47, carrier 1406 is loaded into inserter 1400 laterally as shown.

With reference to FIG. 48, a first disposable portion of inserter 1400 includes adhesive pad 1418 and mount 1408. The second disposable portion of inserter 1400 includes carrier 1406 which removably contains needle hub 1436 and sensor hub 1437 (not shown) which is substantially identical to on body housing 122 described herein. Inserter 1400 further includes body 1402, actuator 1404, and return spring 1409 (not shown). Mount 1408 is removably attached to body 1402. Carrier 1406 can be slid on to body 1402 to transfer needle hub 1436 and carrier 1406 to inserter 1400. As shown in FIG. 48, carrier 1406 can then be removed from inserter 1400. Needle hub 1436 and sensor hub 1437 remain in inserter 1400. Adhesive pad 1418 is then adhesively applied to the skin of a subject. Alternatively, adhesive pad 1418 may be applied to the skin of a subject before attaching body 1402 and mount 1408.

In FIG. 49, actuator 1404 is pressed down, performing a manual insertion of needle hub 1436 and sensor hub 1437, with the needle located in needle hub 1436 and a distal sensor portion penetrating the skin of the subject. When pressure is released from actuator 1404, return spring 1409 (not shown) retracts the needle from the skin of the subject and out of sensor hub 1437. As shown in FIG. 50, body 1402 can be removed from mount 1408, leaving sensor hub 1437 in mounting base 1408. In FIG. 51, in some exemplary embodiments, carrier 1406 is slid on to housing 1402, transferring needle 1436 to carrier 1406. Carrier 1406, with needle 1436, is then removed from housing 1402 and may be disposed of properly, and inserter 1400 is ready to be used again. Communication electronics (not shown) are then attached to mounting base 1408, making electrical contact with sensor hub 1437.

A further embodiment of an inserter is illustrated in FIG. 52. Inserter 1500 is substantially identical to inserters 900, 1000, 1100B, 1200, 1300, and 1400 described herein, with the substantial differences noted herein and illustrated in the accompanying figures.

Inserter 1500 includes a housing 1502, which may be fabricated as a molded plastic tube and may further include a living hinge cap 1504. In some embodiments, a living hinge is a thin flexible plastic junction that connects two mating parts. The hinge keeps the parts attached and may be folded completely without failure to allow the two parts to fully mate.

Cap 1504 may be further provided with a cutout portion to provide access to the index finger and restrict the insertion motion along a desired axis. Cap 1504 is closed up and bonded to the housing through chemical or ultrasonic bonding after the bellow-button assembly (described herein) is provided.

Inserter further includes bellows 1506, which, in some embodiments, is constructed from molded thin wall plastic with an integrated compression spring which collapses during the insertion action, and which provides the force to retract sharp 1524 after insertion. Bellows 1506 also hides sharp 1524 from exposure. The top portion 1520 of the bellows 1506 is secured to button 1514, and bottom portion 1521 is secured to housing 1502.

A button 1514 provides the capability of the user to insert on body housing 122 into the skin of the subject. Button 1514 may be fabricated from plastic and may further include anti-rotation features, e.g., recess 1515 which glides along longitudinal ridge 1517, restricting motion to the desired longitudinal axis. Needle hub 1536 is glued or directly molded onto button 1514. Sharp 1524 is securely held on to on body housing 122, as described herein (See, e.g., FIGS. 11-13).

An adhesive patch 1518 secures on body housing 122 to the skin of the subject. In some embodiments, the adhesive patch 1518 includes a high-tack (i.e., high strength adhesive) region for contact with the skin. A protective liner is provided for removal prior to insertion. On the side of the adhesive patch facing inserter 1500, low-tack region 1530 is provided on the periphery of the patch to allow easy removal of housing 1502 after insertion is completed. A high-tack region 1532 is provided in the center portion of the patch to secure on body housing 122 in place.

Referring to FIGS. 53-55, inserter kit 1600 is illustrated with inserter 2310 and an adhesive mount 2312 removably attached to the bottom thereof. Inserter kit 1600 is further described in U.S. Pat. No. 7,381,184, which is incorporated by reference herein for all purposes.

After preparing an insertion site on the skin, typically in the abdominal region, the user removes a liner (not shown) from adhesive mount 2312 to expose the bottom surface and a portion of the top surface of an adhesive tape 2320 located beneath mount 2312. Mount 2312, with inserter 2310 attached, is then applied to the subject's skin at the insertion site. Actuator button 2324 is depressed, causing inserter 2310 to fire, thereby inserting sensor 2314 into the subject's skin with a predetermined velocity and force. Once sensor 2314 has been inserted into the skin, the patient removes inserter 2310 from mount 2312 by pressing release tabs (not shown) on opposite sides of inserter 2310 and lifting inserter 2310 away from mount 2312.

Once inserter 2310 is removed from mount 2312, communications electronics (not shown) can be slid into place. The circuitry of the communications electronics device makes electrical contact with the contact pads on sensor 2314 after the communications electronics is fully seated on mount 2312. Once initialization and synchronization procedures are completed, electrochemical measurements from sensor 2314 can be sent wirelessly from the communications electronics to a receiver unit.

In some embodiments, inserter kit 1600 is assembled from the following components: housing 2334, actuator button 2324, drive spring 2336, shuttle 2338, introducer sharp 2340, sensor 2314, retraction spring 2342, inserter base 2344, upper liner (not shown), adhesive mount 2312, adhesive tape 2320, and lower liner (not shown).

Shuttle 2338 is slidably and non-rotatably constrained on base 2344 by arcuate guides 2360. Shuttle 2338 is generally formed by an outer ring 2362 and an inner cup-shaped post 2364 connected by two bridges 2366. Bridges 2366 slide between the two slots (not shown) formed between guides 2360 and allow shuttle 2338 to travel along guides 2360 without rotating. Retraction spring 2342 is captivated at its outer circumference by guides 2360, at its bottom by the floor 2370 of base 2344, at its top by bridges 2366, and at its inner circumference by the outer surface of shuttle post 2364. Drive spring 2336 is captivated at its bottom and outer circumference by the inside surface of shuttle post 2364, at its top by the ceiling 2372 inside actuator button 2324, and at its inner circumference by stem 2374 depending from ceiling 2372. When drive spring 2336 is compressed between actuator button 2324 and shuttle 2338 it urges shuttle 2338 towards base 2344. When retraction spring 2342 is compressed between shuttle 2338 and base 2344, it urges shuttle 2338 towards actuator button 2324.

Retraction spring 2342 will return shuttle 2338 to the neutral position as shown after firing, but without sensor 2314 which remains inserted in subject's skin. Drive spring 2336 is preferably designed to be stiffer than retraction spring 2342 so that shuttle 2338 oscillations are quickly dampened out, and so introducer sharp 2340 does not return to sensor 2314 or the patient to cause injury. With sensor 2314 inserted in the subject's skin, inserter 2310 can be removed from mount 2312 and then lifting inserter 2310 away from mount 2312. Introducer sharp 2340 remains protected inside housing 2334 during disposal of inserter 2310. Communications electronics can now be slid into place on mount 2312 as previously described.

In some embodiments, a proximal portion of stem 2374 is enlarged to create an interference fit with the coils of spring 2336. For example, one or more laterally extending ribs 2610 are added to stem 2374. The interference fit between ribs 2610 and spring 2336 is typically provided at the proximal (top) coils of spring 2336.

The diameter of the coils of spring 2336 increases slightly when compressed and decreases slightly when extended. Ribs 2610 on stem 2374 provide greatest interference when spring 2336 is extended. The interference fit provides increased stability of shuttle 2338 during insertion. In some embodiments, the interference fit prevents or minimizes distal movement of spring 2336, which may cause impact of spring 2336 against shuttle 2338 and the end of the distal travel of these components.

Referring to FIGS. 56-70, in another exemplary embodiment, inserter 2600 generally includes: actuator button 2602 (FIG. 57), shuttle 2604 (FIG. 58), inserter sharp 2610 with skin piercing edge 2612 (FIG. 58), retraction spring 2608 (FIG. 59), sensor 2614 (FIG. 60), housing 2616 (FIG. 61), and base 2618 (FIG. 62). It is understood that inserter 2600 may include additional or fewer components than described herein. Inserter 2600 is substantially identical to inserter 1600 described herein, with the substantial differences noted herein and illustrated in the accompanying figures. The assembly of the different components of inserter 2600 is depicted in FIGS. 63-65. As shown in FIG. 63, actuator button is adapted to be slidably inserted through an opening in shuttle 2604 where it locks into position. Further, as shown in FIG. 64, retraction spring 2608 is adapted to be inserted into a second opening on the opposite side of shuttle 2604. Additionally, in this view, sensor 2614 has been attached to inserter sharp 2610. As shown in FIG. 60, sensor 2614 incorporates a biasing arm 2615 that positively seats the sensor 2614 into the inserter sharp 2610. This allows the inserter sharp 2610 and sensor insertion portion 30 to be smaller, reducing the trauma and pain to the subject. Any number of the aforementioned sensor connection methods can be utilized in conjunction with inserter 2600. For example, inserter sharp 2610 may be provided with rails and dimples, as previously described, in order to retain sensor 2614, the sharp 2610 having a diameter of about 20 to about 26 gauge, e.g., 21 gauge to about 25 gauge, where in certain embodiments the sharp is 21 gauge or 23 gauge or 25 gauge. Such sharp may be used with a sensor having a width or diameter—at least the portion that is carried by the sharp—of about 0.20 mm to about 0.80 mm, e.g., about 0.25 mm to about 0.60 mm, where in some embodiments the width or diameter of at least a portion of a sensor is 0.27 mm or 0.33 mm or 0.58 mm.

FIG. 66 depicts a cross-sectional view of the assemblage of FIG. 65 after inserter 2600 has been fully assembled (joining housing 2616 to base 2618). As depicted, retraction spring 2608 is surrounded by guides 2622 on its sides and by shuttle 2604 and base 2618 when inserter 2600 is assembled. Additionally, shuttle 2604 is adapted to slidably move on rails (not shown) within base 2618, thereby allowing it to move in a linear direction when actuator button 2602 is depressed. FIG. 66 depicts the actuator button 2602 locked onto the shuttle 2604 using the first of two detent grooves 2607. In this configuration, the shuttle 2604 and actuator button 2602 are in a locked state relative to the housing 2616 and base 2618, preventing accidental deployment of the shuttle during shipping and handling. This configuration also allows for significantly smaller packaging, resulting in lower shipping costs and improved bulk process efficiencies such as sterilization. FIG. 67 depicts the actuator button 2602 locked onto the shuttle 2604 using the second of two detent grooves 2607. In this configuration, the shuttle is ready to be deployed. The actuator button 2602 is moved to the second detent groove 2607 by a user pulling axially on the actuator button 2602 and housing 2616.

FIGS. 68-70 illustrate the steps utilized to deploy sensor 2614 using inserter 2600. FIG. 68 depicts inserter 2600 in a first configuration. The upward force exerted by retraction spring 2608 on shuttle 2604 (and consequently actuator button 2602) keeps inserter 2600 in its cocked position in the first configuration. As actuator button 2602 is pressed by a user against the bias of retraction spring 2608, it exerts a downward force on shuttle 2604 and retraction spring 2608. Introducer sharp 2610, on which sensor 2614 is mounted, is consequently driven downward and into the skin of the subject (e.g., to a second configuration). Skin piercing edge 2612 pierces the skin of the subject and allows sensor 2614 to be properly inserted, as shown in FIG. 69.

As the force is removed from actuator button 2602, retraction spring 2608 exerts an upward force on shuttle 2604, thereby causing introducer sharp 2610 to return proximally to its original position inside of housing 2616 (e.g., to the first configuration). Sensor 2614 remains implanted in the patient's skin, as shown in FIG. 70. In this position, the plunger is bent approximately 90 degrees by the user, which prevents further use of the device, and provides obvious visual and tactile indications that the device is used and ready to be disposed.

In another aspect of the disclosed subject matter, an inserter assembly, as illustrated in FIG. 71, is provided which is useful for installing a medical device, such as an analyte sensor, in the skin of a subject. Inserter assembly 4300 may include an inserter, a medical device, such as an analyte sensor, and a mount for positioning the medical device at least partially in or on the skin of the subject. In some embodiments, the mount is a support structure, plate and/or member which is attached, adhered, or otherwise secured to the skin of the subject. The mount may be applied to the skin of the subject simultaneously with the medical device by the inserter. In other embodiments, the mount is installed after or before installation of the medical device. A mount may be applied by the inserter or separately. The mount may include features or structures (e.g., adhesive, guides, barbs, tabs, etc.) to maintain the sensor in position with respect to the skin after insertion and/or maintain the sensor in relative position with respect to the sensor control unit.

Inserter assembly 4300 is useful for analyte measurement systems, e.g., glucose measurement systems which include an on-body unit that may be assembled on the skin of the subject. For example, the on-body unit may include a sensor and a sensor control unit. The sensor is typically installed in the patient. Subsequently, the sensor control unit is installed and coupled to the sensor. In other embodiments, the sensor control unit is installed at the patient first, followed by installation of the sensor, which is then coupled to the sensor control unit. In yet other embodiments, the sensor and sensor control unit are simultaneously installed and coupled. An optional mount may or may not be used to position the sensor and/or the sensor control unit.

Generally, the inserter assembly 4300 is useful to install a sensor in the skin of a subject. A sensor (not shown) may be preloaded within inserter 4310 prior to installation. After preparing an insertion site on the skin of a subject, the user removes an upper liner 4316 and lower liner 4318 from mount 4312 to expose the bottom surface and a portion of the top surface of an adhesive tape located on the bottom surface of the mount 4312. Mount 4312, with inserter 4310 attached, is then applied to the subject's skin at the insertion site. In some embodiments, the mount 4312 is first attached, and then the inserter is coupled to or positioned within and/or adjacent to the mount 4312. The inserter includes an actuator button 4324 (see FIG. 74) to be depressed causing inserter 4310 to fire, thereby inserting a sensor into the user's skin. As will be described herein, certain embodiments install the sensor with a predetermined velocity and force upon actuation. In some embodiments of the disclosed subject matter, the inserter includes a safety member to impede actuation of the inserter as described below.

In some embodiments, the sensor 4314 remains positioned at the mount 4312 by one or more positioning techniques. For example, as illustrated in FIG. 72, sensor 4314 has a surface 4356 that extends orthogonally from main surface 4346. Surface 4356 may include an adhesive portion that contacts the subject's skin 4328 or the mount 4312. In some embodiments, the raised end stop 4444 of mount 4312 is provided with a raised bead or bump which is received in an aperture in sensor 4314. Following insertion of the sensor 4314 into the skin, the user may remove the inserter 4310 from mount 4312, e.g., by pressing release tabs 4326 on opposite sides of inserter 4310 and lifting inserter 4310 away from mount 4312. In some embodiments, the inserter 4310 is retained by other techniques, e.g., a friction-fit or a snap-fit with the mount 4312.

Once inserter 4310 is removed from mount 4312, a sensor control unit 4330 can be positioned into place with respect to the mount 4312. The circuitry of sensor control unit 4330 makes electrical contact with the contacts on sensor 4314 after sensor control unit 4330 is seated on mount 4312. For example, as shown in FIG. 72, seal has an exterior wall for surrounding electrical contacts on sensor 4314 (not shown in FIG. 72), and interior walls for isolating electrical contacts from each other. In some embodiments, rails on sensor control unit 4330 are slidable within corresponding rails or grooves 4434 on mount 4312.

In some embodiments, initialization and synchronization procedures are completed, and then electrochemical measurements from sensor 4314 can be provided from sensor control unit 4330 to a monitor unit, such as, e.g., portable monitor unit 4332, shown in FIG. 73. Sensor control unit 4330 and monitor unit 4332 communicate via connection 20 (in this embodiment, a wireless radio frequency (RF) connection). Communication may occur, e.g., via RF communication, infrared communication, Bluetooth® communication, Zigbee® communication, 802.1x communication, or WiFi communication, etc. In some embodiments, the communication may include a radio frequency of 433 MHz, 13.56 MHz, or the like. In some embodiments, communication between sensor control unit 4330 and monitor unit 4332 may include radio frequency identification (RFID) techniques, and may be active RFID or passive RFID, where, in some embodiments, passive RFID technology and the respective system components include the necessary components therefor. For example, in one embodiment, the monitor unit may include a backscatter RFID reader configured to transmit an RF field such that when the sensor control unit is within the transmitted RF field, an antenna is tuned and in turn provides a reflected or response signal (for example, a backscatter signal) to the monitor unit. The reflected or response signal may include sampled analyte level data from the analyte sensor. Additional exemplary details for various embodiments can be found in, e.g., U.S. patent application Ser. No. 12/698,124 filed Feb. 1, 2010, the disclosure of which is incorporated by reference herein for all purposes.

Sensor 4314, mount 4312 and sensor control unit 4330 can remain in place on the subject for a predetermined maximum period of time that may include hours, days, weeks, or a month or more. These components are then removed so that sensor 4314 and mount 4312 can be properly discarded in some embodiments. The entire procedure above can then be repeated with a new inserter 4310, sensor 4314 and mount 4312, reusing sensor control unit 4330 and monitor unit 4332. In other embodiments, inserter 4310 is reusable.

Referring to FIG. 74, the inserter assembly 4300 according to one embodiment can be assembled as shown from the following components: housing 4334, actuator button 4324, drive spring 4336, shuttle 4338, introducer sharp 4340, sensor 4314, retraction spring 4342, inserter base 4344, upper liner 4316, adhesive mount 4312, adhesive tape 4320, and lower liner 4318.

In some embodiments, sensor main surface 4346 is slidably mounted between U-shaped rails 4348 of introducer sharp 4340. In addition to the holding members disposed on the introducer, as described above, retention techniques are provided in certain embodiments to retain the sensor 4314 in position on sharp 4340 during storage of the inserter 4300 and/or during insertion of the sensor 4314 into the subject's skin. For example, a sensor dimple (not shown) is provided which engages an introducer dimple (also not shown). Introducer sharp 4340 can be mounted to face 4354 of shuttle 4338, such as with adhesive, heat stake or ultrasonic weld.

In some embodiments, shuttle 4338 can be slidably and non-rotatably constrained on base 4344 by arcuate guides 4360. The shuttle can be generally formed by an outer ring 4362 and an inner cup-shaped post 4364 connected by two bridges 4366. Bridges 4366 can be configured to slide between the two slots 4368 formed between guides 4360 and allow shuttle 4338 to travel along guides 4360 without rotating. In some embodiments, a retraction spring 4342 is provided, which can be captivated at its outer circumference by guides 4360, at its bottom by the floor 4370 (see FIG. 75) of base 4344, at its top by bridges 4366, and at its inner circumference by the outer surface of shuttle post 4364. In some embodiments, a drive spring is provided for advancing the sensor 4314 and the sharp 4340 into the skin of the subject. For example, drive spring 4336 is captivated at its bottom and outer circumference by the inside surface of shuttle post 4364, at its top by the ceiling 4372 (see FIG. 75) inside actuator button 4324, and at its inner circumference by stem 4374 depending from ceiling 4372. In some embodiments, a drive spring is omitted from the inserter assembly. In such case, for example, sensor 4314 and sharp 4340 are distally advanced by manual force applied by a user.

When drive spring 4336 is compressed between actuator button 4324 and shuttle 4338 it can urge shuttle 4338 towards base 4344. When retraction spring 4342 is compressed between shuttle 4338 and base 4344, it urges shuttle 4338 towards actuator button 4324.

When sensor 4314, introducer sharp 4340, shuttle 4338, retraction spring 4342, drive spring 4336 and actuator button 4324 are assembled between base 4344 and housing 4334 as shown in FIGS. 74-75 and described above, housing 4334 is snapped into place on base 4344. Base 4344 is held onto housing 4334 by upper base barbs 4390 that engage upper openings 4392 in housing 4334, and lower base barbs that engage lower openings in housing 4334. Further details regarding the construction and operation of inserter 4300 is provided in U.S. Pat. No. 7,381,184 which is incorporated by reference herein in its entirety for all purposes.

In some embodiments, retention techniques and/or structures are provided to assist in supporting the sensor 4314 with respect to the sharp 4340 during storage and insertion. As illustrated in FIGS. 76-90, retention mechanisms are provided which are located on the sensor and/or the sharp.

FIGS. 76-77 illustrate a sensor 4514 which is provided with one or two laterally extending tabs 4560. Tabs 4560 engage the rails 4548 of the sharp 4540 for retention. In some embodiments, a radiused edge on the ears allow them to be formed in two punch operations, e.g., a hole punch and a straight cut. A gap between left hard-stop 4549 and the top of sensor 4514 produces, during firing, a moment that biases the sensor tip into the sharp channel. During deployment, the sensor deflects to disengage the sharp.

FIGS. 78-79 illustrate an inserter having a sensor retention mechanism in accordance with a further embodiment of the subject disclosure. Sharp 4640 is provided with a clip 4660 that engages a retention window 4662 at the top of sensor 4614 to provide retention of sensor 4614 in sharp 4640, and vertical registration. Two drive blocks 4659 and 4661 on carrier 4654 traverse sharp 4640 to engage the top edge of sensor 4614. There is a gap between the left drive block 4659 and the top edge of sensor 4614. Right drive block 4661 is in contact with the top edge of sensor 4614. During insertion, the upward drive force of the skin on sensor 4614 produces a clock-wise rotational moment on sensor 4614 that biases sharp 4614 into the sharp channel.

The clip feature 4660 and the window 4662 can be moved to the left to bias the tip of the sensor 4614 into the channel during shipping. During deployment, the sensor 4614 and the clip 4662 deflect to transfer the sensor 4614 to the mount 4312.

FIG. 80 illustrates a further embodiment of a sensor retention technique. In particular, sensor 4714 is provided with a retention member 4760, which extends from the contact portion 4732 of the sensor 4714. Retention member 4760 is resiliently biased in the position as shown. When the sensor 4714 is inserted within the sharp (not shown), the retention member engages the inner portion of rails (not shown) of the sharp, and provides a retention force to the sensor 4714.

FIG. 81 illustrates another embodiment of a sensor retention technique. Sensor 4814 is provided with a dimple 4860 which is thermally formed. As shown in FIG. 82, a raised bump 4864 on the sharp 4840 frictionally contacts thermally formed dimple 4860 in order to provide retention force to the sensor 4814. In some embodiments, raised bump is formed using heat. In another embodiment, a raised bump is formed on the sensor and the dimple is formed on the sharp.

FIGS. 83-84 illustrate an aperture 4960 which is formed in the contact portion of the sensor 4914. A raised bump or tab 4962 is provided on the sharp 4940. The interaction of the tab 4962 within the aperture 4960 of the sensor 4914 assists in retaining the sensor 4914 within the inserter.

FIGS. 85-86 illustrate a technique for retention of the sensor 5014 which is similar to the techniques illustrated in FIGS. 81-84. For example, a raised bump 5062 is provided on sharp 5040 which engages the contact portion 5032 of the sensor 5014. In such configuration, the raised bump 5062 creates a bias force against the contact portion 5032. Such force acts as a frictional force to assist retention of the sensor 5014 within the sharp 5040.

FIGS. 87 and 88 illustrate sensors having retention members which engage a raised post or button on the sharp. FIG. 87 illustrates that contact portion 5132 of sensor 5114 includes a pair of “pincer fingers” 5160 having a substantially arcuate configuration which surround and engage a post 5162 provided on the sharp. Similarly, FIG. 88 illustrates sensor 5214 having a pair of proximally extending arms 5260, which engage a post 5262 on the sharp.

FIG. 89 illustrates a sensor 5314 having a laterally extending arm 5360 which defines a channel 5364 between the arm 5360 and the contact portion 5332 of the sensor 5314. As illustrated in the figure, a post 5360 may be positioned within the channel 5364, and provides frictional resistance to maintain the sensor 5314 within the sharp.

FIG. 90 illustrates a sensor 5414 having a proximally extending arm 5460 which defines a channel 5362 between the arm 5460 and the contact portion 5432 of the sensor 5414. As illustrated in the figure, a tab 5364 is provided on the arm 5460 and is received within a gap provided in the rails of the sharp. This interaction of the tab 5364 with the gap provides frictional resistance to maintain the sensor 5414 within the sharp.

FIGS. 91-92 refer to sensor retention techniques which include a retention member which provides a frictional force substantially normal (perpendicular) to the surface of the sensor. FIGS. 91 and 92 illustrate a retention member which is provided within the housing 5534 of the inserter 5510. For example, the retention member 5560 may extend distally from the housing 5534 and includes a laterally extending tab 5562 which contacts the sensor 5563 and provides a frictional force to assist retention of the sensor within the sharp 5540.

FIGS. 93 and 94 illustrate a retention member which is provided with the base 5644 of the inserter 5610. For example, retention member may include a cantilever 5660 which extends proximally from base 5644 of the inserter 5610. Cantilever 5660 may include a laterally extending member 5662 which contacts the sensor 5661 and provides a frictional force to assist retention of the sensor within the sharp 5640. When the carrier 5666 bottoms down, the cantilever 5660 ceases contact, and release of the sensor occurs.

FIGS. 95 and 96 illustrate a resilient or elastomeric member which is disposed within the housing 5734 of the inserter 5710. For example, elastomeric member 5760 is manufactured from TPE and presses against the sensor and the resulting friction keeps the sensor in place. The TPE material creates a higher friction with respect to the sensor, and therefore requires less pressure to produce the sensor holding force. When the inserter 5710 is actuated, the frictional forces are directed upward keeping the sensor inside the sharp. When the carrier bottoms down, the contact with the friction rib ceases and the sensor releases to the mount. In some embodiments, the elastomeric member 5760, or rib, is produced with a second-shot injection molded process or press-fit into housing 5734.

FIGS. 97 and 98 refer to retention members which provide a frictional force in a substantially coplanar direction to the surface of the sensor. FIG. 97 illustrates a retention member or cantilever 5860 which is biased against the side edge of the contact portion 5832 of the sensor 5814. In some embodiments, cantilever 5860 is provided on the carrier or sharp (not shown). FIG. 98 illustrates a sensor retention technique which includes a retention member, or cantilever 5960 which is biased against the sensor, as described in FIG. 97. Cantilever 5960 includes a laterally extending portion which is at least partially received in an optionally provided notch 5964 in sensor 5914. In addition, a second retention member, or retention spring 5990, is provided which is biased to engage the front surface of the sensor. In some embodiments, retention spring 5990 is partially received in cut-out 5994 (or a slot) to capture the sensor.

In some embodiments, an inserter assembly is provided which includes a reusable inserter apparatus. Repeated uses of the inserter include the use of a removable and exchangeable sensor and sharp which may be coupled to the inserter during deployment of the sensor, and in which the sharp is removed and discarded after deployment.

FIGS. 99-101 illustrate a system of sharp/sensor packs 6002 which contain a plurality of sensor/sharp combinations 6006. As illustrated in FIGS. 99 and 101, a support is provided which includes a plurality of trays 6004 which are useful for containing the sensor/sharp configuration 6006, and well as a desiccant 6010 which is contained in a chamber 6008. A well 6012 is provided on one side of the tray 6004 to accommodate the sensor sharp for installation into a patient. A cover, such as a foil lid 6014 is applied to the top of the support to maintain the sterility of the sensor/sharp combination until installation in a subject. FIG. 100 is a perspective view which illustrates an exemplary configuration of pack 6002. The foil lid 6014 for each of trays 6004 may include a tab 6016 to facilitate removal of the lid from the tray 6004 (FIGS. 100, 101).

FIGS. 102-105 illustrate a plurality of reusable inserters which are useful in combination with the sharp/sensor packs 6002 described herein. FIG. 102 illustrates an inserter 6030 which includes a body portion 6032, a loading or cocking structure 6036, and an actuator button 6040 for deploying the sensor into the skin of the subject. The advancement structure of inserter 6030 may include a cocking structure which is pulled to arm, e.g., by withdrawing the cocking structure 6036 from the housing 6032; which is pushed to arm, e.g., by depressing the cocking structure 6036 into the housing 6032; or which is rotated to arm, e.g., by rotating the cocking structure 6036 in a rotational movement parallel to the longitudinal axis of the inserter 6030, or perpendicular to the longitudinal axis of the inserter 6030. The driving mechanism of inserter 6030 is substantially similar to the driving mechanisms as disclosed in U.S. Patent Publication 2008/0082166, now U.S. Pat. Nos. 8,167,934, 6,197,040, or U.S. Pat. No. 4,976,724, which are incorporated by reference in their entirety herein for all purposes.

To insert the sharp/sensor combination into the inserter 6030, the foil lid is removed from sharp/sensor pack 6002. The distal end portion 6034 of the inserter 6030 is positioned within the walls 6004 of the tray 6002, as indicated in the direction of arrow E. The distal end portion 6034 comes to rest on the upper surface of desiccant chamber 6008, such that the insertion sharp remains exposed.

FIG. 103 illustrates an inserter 6130 substantially identical to the inserter 6030 described herein. Inserter 6130 is used in connection with sharp/sensor trays 6102. Trays 6102 include a desiccant chamber 6108 which is located in the center portion of the tray 6102. Accordingly, a channel 6112 surrounds the periphery of desiccant chamber 6108. When the inserter 6130 is applied to the sharp/sensor tray 6102, the distal end portion 6134 can be positioned within the channel 6112. As illustrated in FIG. 103, this configuration allows the sensor and sharp to be completely housed within the inserter 6130.

FIG. 104 illustrates an inserter 6230 substantially identical to the inserters 6030 and 6130 described herein, with the differences noted herein and illustrated in the figures. Inserter 6230 may be used in connection with sharp/sensor trays 6204. The tray 6204 and inserter 6230 are sized and configured such that tray 6204 is capable of being positioned entirely within the distal end portion 6234 of inserter 6230. One or more support struts 6220 are provided adjacent the distal end portion 6234 to stabilize the inserter with respect to any surface on which the inserter 6230 and trays 6204 are placed for the insertion step. Support struts 6220 may also secure inserter 6230 to an adhesive mount (not shown) during insertion.

FIG. 105 illustrates an inserter 6330 which is substantially identical to the inserters 6030, 6130, and 6230 described herein, with the differences noted herein and illustrated in the figures. Inserter 6330 may be used in connection with sharp/sensor tray 6304. In some embodiment, tray 6304 includes a distally projecting handle portion 6340 which may be grasped by the user to facilitate insertion of the sharp/sensor into the inserter.

FIGS. 106-107 illustrate an exemplary sharp/sensor combination for use with inserters 6030, 6130, 6230, and 6330 described herein. Sharp 6440 includes side rails 6448 for sliding reception of a sensor therein. A locking tab 6450 is also provided on the proximal portion of the sharp and includes cut-out portion 6452 for interlocking with the carrier of the inserter 6030 (or 6130, 6230, or 6330). As illustrated in FIGS. 108-112 carrier 6466 includes reception structure for mating reception with the sharp 6440. For example, carrier 6466 may include a pair of walls 6480 providing a channel 6478 in which said sharp 6440 may be positioned. Walls 6480 are provided with cutout portions 6482 for reception of undercut portion 6452 in locking tab 6450. A pair of securement members 6484 are movably mounted on the carrier 6466. For example, members 6484 are biased via a spring 6486 towards a center portion of the carrier 6466. As illustrated in FIG. 111, securement members 6484 may be moved outwardly against the spring bias to allow for the insertion of the locking tab 6450 into the cutout portion 6482 of the carrier. Securement member 6484 is subsequently released and returns to a position to engage the undercut portion 6452 to prevent accidental removal of the sharp and sensor from the inserter (FIG. 112). It is understood that coupling of the sharp and carrier may be provided by alternative techniques such as frictional fit, snap-fit, bayonet mounts, magnetic coupling, etc.

FIGS. 113-117 illustrate a further embodiment of the subject disclosure that is reusable, and useful with the sharp/sensor packs discussed herein. FIG. 113 illustrates a sensor pack 6504 which is similar to the sensor packs described herein. Sharp/sensor pack 6504 also includes one or more reinforcing ribs 6574 to prevent accidental deformation of the pack 6504 when the sensor is being inserted into the inserter.

As illustrated in FIG. 114, inserter 6530 is provided which is substantially similar to inserters 6030, 6130, 6230, and 6330 described herein, with the differences noted herein or illustrated in the figures. Inserter 6530 includes a carrier (not shown) for coupling with a sharp/sensor combination. As illustrated in the figure, inserter 6530 is lowered onto sharp/sensor pack 6504 in order to couple the sharp 6506 with the carrier. As illustrated in FIG. 115, inserter 6530 which now contains the sharp/sensor 6506 is positioned over the mount 6512. Mount 6512 may include an adhesive for securement to the skin of the subject. Inserter 6530 includes a locking structure 6526 which allows for temporary engagement of the inserter 6530 with the mount 6512.

As illustrated in FIG. 116, the sensor is deployed by depressing actuation button 6532 on the inserter 6530 to advance the sensor into the skin by use of an internal drive mechanism, such as, e.g., a spring. It is understood that the above-described process may alternatively be carried out by using an inserter which allows the user to provide a manual distal force for deployment of the sensor.

Following installation of the sensor, inserter 6530 is decoupled from the mount, e.g., by depressing locking buttons 6526 on inserter 6530. Once the inserter 6530 is separated from the mount, the user may remove and discard the sharp. In some embodiments, inserter 6530 includes a sliding lever 6540 which allows for removal of the sharp. It is understood that disengagement of the sharp from carrier may be executed in one of several ways, e.g., sliding switch allows securement member (discussed herein) to slide outwardly and allow disengagement of the contact portions 6483 of the securement members 6484 from the undercut portions 6452 of locking tab 6450.

FIG. 118 illustrates an inserter 6630 and engagement structure for mounting on mount 6612. Inserter 6630 includes a body portion 6640 which is configured to advance a sharp/sensor cartridge into the skin S of a subject along longitudinal axis LON. The longitudinal axis LON may be substantially perpendicular to the skin surface. In some embodiments, axis LON forms an acute angle with the skin surface. Mount 6612 and inserter 6630 are each provided with complementary locking structures 6662 on the mount 6612 and 6664 on the inserter. Inserter is advanced laterally (direction LAT) over mount 6612. Inserter 6630 may be locked in place by pivoting locking structure 6632 about pivot 6626. Following such pivoting action, the engagement portion 6666 of locking structure 6632 is received in recess 6668 in mount 6612. Securement of the inserter to the mount is further provided by insertion of the sharp/sensor cartridge 6650 between the inserter 6630 and the mount 6612. For example, cartridge 6650 includes raised tabs 6654 which are slidable within complementary grooves 6652 provided on the inserter 6630 and mount 6612. Insertion of the cartridge is carried out in a direction perpendicular to the direction in which the inserter is attached to the mount, e.g., a direction perpendicular to the plane of the page.

FIGS. 119-121 illustrate another embodiment of an inserter in accordance with the disclosed subject matter. Inserter 6730 is useful for advancing a medical device, such as an analyte sensor, into the skin of a subject. Inserter 6730 includes a hammer member 6760 which accumulates advancement energy to provide a more rapid and powerful advancement stroke. As illustrated in FIG. 119, hammer member 6760 is initially positioned somewhat askew with respect to the longitudinal axis of the device. As the alignment trigger 6734 is advanced distally, alignment sleeves 6736 gradually pivot the hammer member 6760 into a longitudinal configuration. As the hammer member 6760 is being pivoted into position, the advancement spring continues to be compressed. With reference to FIG. 120, the hammer member 6760 is pivoted into alignment with the central bore of the inserter 6730, e.g., along the longitudinal axis represented by the arrow. Consequently, the tension of advancement spring 6742 is immediately released, which permits rapid distal movement of the hammer member 6760. Hammer member 6760 contacts carrier 6744, which in turn contacts sharp/sensor combination 6718 to provide distal movement.

As illustrated in FIG. 121, a ledge or lateral member 6726 is provided with the internal bore of the inserter. As the hammer member 6760 advances distally, the distal surface of the hammer member contacts the ledge 6726. Interengagement of the hammer member 6760 and the ledge 6726 inhibits further distal travel of the hammer member 6760.

FIG. 122 illustrates an exemplary embodiment of a simplified unit, or cartridge 6800, which holds certain components for sterility and subsequent interaction with the subject. In some embodiments, the components include the sharp 6840, the housing 6860, the sensor 6814. The cartridge 6800 may be used in connection with any of the inserters 6030, 6130, 6230, 6330, 6530 and/or 6730 described herein. In some embodiments, the cartridge includes a housing and a lid which contain the sharp and sensor therein. In some embodiments, a resilient member or other cantilever structure is used to maintain the alignment of the sharp and sensor within the cartridge. Interaction of the cartridge with the inserter advances the sensor and sharp such that the sensor is installed at the subject.

As illustrated in FIGS. 123-124, the sharp 6840 and sensor 6814 may sit in a recessed portion of the disposable cartridge 6800. A spring finger or cantilever 6876 on the housing lid maintains a load on the sharp 6840 and sensor 6814 to keep it depressed in the cavity. Attachment for a lid to the base of the cartridge housing 6860 is not shown in the figure above, but methods such as snaps, heat stake, or ultrasonic welding may be used to join the two housings in assembly. The sensor 6814 is contained within the sharp 6840, laterally by the two rounded ends 6848 of the sharp, and in the orthogonal lateral direction (in relation to the views shown above), by two bent tabs 6849 on the sharp 6840 and the cartridge housing base cavity. The sharp is held in its lateral position by not only the cavity, but also by the raised pyramid feature 6878 shown on the housing base 6870. In the figure above, the locating pyramid sits in the opening 6882 created from the bent tab in the sharp. The engagement features to locate/attach/engage the cartridge to the inserter portion of the device are not shown in the figures above, but may include such features as illustrated in FIGS. 106-112 above.

As illustrated in FIGS. 125 and 126, when the cartridge 6800 is loaded onto the reusable inserter part of the device, the sharp is raised out of its cavity by stationary elements built onto the inserter (not shown). Features from the reusable portion of the inserter enter through the two shorter slots shown FIG. 122. These features will remain stationary throughout the sensor delivery action of the inserter device.

In the longer middle slot 6866, a stepped feature from the inserter, mates with the opening on the sharp (shown as two holes 6864 in the figure above). The stepped portion of the feature provides a force on the back portion of the sharp to keep it raised against the force of the sprung cantilever 6876 on the housing. This feature of the inserter will move in relation to the cartridge and provide the drive and retraction movement for the sharp through insertion and delivery of the sensor. In some embodiments, the force is transmitted through driving pins which are part of the movable portion of the inserter device. The driving pins protrude through holes 6864. In case of minor misalignment of the driving pins (not shown), ribs on the cartridge housing lid will constrain the sharp from tilting up.

Once the sharp and sensor are raised from the cavity portion of the cartridge, they are no longer constrained by the recessed cavity portion of the housing base and the pyramid feature maintaining the sharp position. The sharp is held in its raised position by the stationary and stepped drive feature of the inserter, balanced with the force of the cantilever finger on the lid housing. The sensor is kept in place by being pinched against the cantilever finger on the housing lid. The sharp is constrained in its retracted position by the mated drive feature of the inserter.

As the inserter is actuated, the mated inserter drive feature drives the sharp downward as it moves through the longer slot shown in the figure above (see FIGS. 127-129). The driven sharp slides along the stationary ribs of the inserter, ribbed features built into the cartridge housing, and the housing lid cantilever finger. The friction force of the cantilever keeps the sensor up against the ‘drive block’ and bends in the sharp sheet metal to assure the tail is not exposed from the sharp channel during insertion. In some embodiments, the ‘drive block’ features are longitudinal constraints either built into the sharp or the carrier which constrain the sensor from proximal movement with respect to the sharp. In another embodiment, the drive block features are protrusions on the carrier or bends on the sharp which push the sensor as the sharp is propelled distally.

The sensor is kept from popping over the drive block features by the stationary ribs built into the housing lid. As the cantilever slides over the top edge of the sensor, the retention force is relieved from the sensor, and it can be captured onto the mount portion of the device with relatively little force. Alternately, if geometry permits, and the finger is positioned appropriately, the pinching of the cantilever on the sharp may provide enough resistance on the return motion of the sharp to keep the sensor in its inserted position even without a capture device on the mount. The inserter drive feature then retracts the sharp, leaving the sensor in place on the mount portion (that is attached to the skin) of the device.

The cartridge can be removed from the inserter. As the cartridge is removed, the force from the housing lid cantilever presses the sharp back into the recess on the cartridge base housing. The base housing is removed and can be discarded.

Another embodiment of the cartridge is illustrated in FIGS. 131-137. As illustrated in FIG. 131, the sharp 6940 and sensor 6914 in this embodiment abuts ribs 6972 and 6974 and on insertion plane to which the sharp 6940 will be driven and retracted by the inserter into the skin. The sharp and sensor are held in place by a central cantilever feature 6976 built onto the cartridge lid housing. This cantilever 6976 has geometry such that a vertical portion of the end of the cantilever is butted against the sharp 6940 and sensor 6914.

As illustrated in FIGS. 132 and 133, the cartridge 6900 is loaded onto the inserter, in which a stationary feature on the inserter (not shown) raises the cartridge cantilever so that the ramped portion of the cantilever end feature is now in line with the insertion plane of the sharp. Also, a driving element of the inserter (not shown) fits through the slot opening on the sharp. In the embodiment described herein, a step is not required on the driving element on this design.

As the sharp is driven downward (see, FIGS. 134-135), the cantilever arm 6976 is pushed up, keeping the sensor in position against the sharp 6940. Stationary ribs on the housing lid assure that the sharp 6940 maintains its insertion plane during insertion, and also assures that the pinching force of the cantilever does not cause the sensor to hop the drive block elements integrated into the sharp. The stationary ribs keep the sensor flat against the sharp through the insertion motion.

As illustrated in FIGS. 136-137, the sensor 6914 is captured at the bottom of its motion on the mount, as discussed hereinabove. The drive elements on the inserter retract the sharp 6940 back to its starting position. The cantilever arm 6976 returns to its original unbiased configuration. The cartridge 6900 is removed from the inserter and can be discarded.

It is understood that the subject matter described herein is not limited to particular embodiments described, as such may, of course, vary. It is also understood that the terminology used herein is for the purpose of describing particular embodiments only, and is not intended to be limiting, since the scope of the present subject matter is limited only by the appended claims. 

The invention claimed is:
 1. A method of inserting a medical device into a subject, the method comprising: positioning an insertion assembly on skin of the subject such that an adhesive layer adheres to the skin, the insertion assembly comprising a housing, a torsion spring in a loaded position, a first slidable body having a slot, a second slidable body, a needle coupled with the second slidable body, the medical device, and a rotor having a projection received within the slot; and depressing a button of the insertion assembly, wherein depression of the button releases the torsion spring from the loaded position such that the torsion spring causes rotation of the rotor and projection, and wherein rotation of the rotor and projection causes advancement of the first slidable body and the second slidable body within the housing and advancement of the needle and the medical device through an aperture in the adhesive layer and into the subject, followed by expansion of a compression spring that causes retraction of the needle.
 2. The method of claim 1, wherein a first end of the compression spring is in contact with the first slidable body and a second end of the compression spring is in contact with the second slidable body.
 3. The method of claim 2, wherein the rotation of the rotor and projection advances the first slidable body and the second slidable body simultaneously.
 4. The method of claim 2, wherein movement of the second slidable body away from the skin of the subject retracts the needle from the subject.
 5. The method of claim 2, wherein rotation of the rotor and projection causes advancement of the first slidable body and the second slidable body towards the skin of the subject.
 6. The method of claim 2, wherein the second slidable body comprises a slot, wherein the projection is received within the slot of the second slidable body.
 7. The method of claim 1, wherein the medical device is a sensor.
 8. The method of claim 1, wherein the torsion spring comprises a winding, a first end extending from the winding, and a second end extending from the winding.
 9. The method of claim 8, wherein the first end of the torsion spring engages with the housing and the second end of the torsion spring engages with the rotor.
 10. The method of claim 8, wherein the torsion spring winding is helical.
 11. The method of claim 1, wherein the slot comprises a straight portion.
 12. The method of claim 1, wherein the slot comprises a straight portion and a curved portion.
 13. The method of claim 1, wherein the housing comprises a recess in which the rotor is received.
 14. The method of claim 1, wherein a force applied by the projection against a wall of the slot causes advancement of the first slidable body.
 15. The method of claim 1, wherein the slot in the first slidable body with the projection received within the slot allows the first slidable body to advance towards the skin of the subject.
 16. The method of claim 1, further comprising coupling on-body electronics to the adhesive layer.
 17. The method of claim 16, further comprising wirelessly communicating, by the on-body electronics, data from the medical device.
 18. The method of claim 1, wherein the projection rotates in a circular path.
 19. The method of claim 1, wherein the rotor has a cylindrical shape.
 20. The method of claim 1, wherein the torsion spring has a center aperture that receives a second projection of the insertion assembly, further wherein the torsion spring rotates around the second projection. 